Dr Dingle's Blog

Walking

Walking

 

“Walking is man's best medicine.”- Hippocrates

Walking is probably the most underestimated and undervalued activity we do. We often take it for granted until we have some injury or can no longer walk, while it is probably the single most important activity that keeps us healthy, alive and adds to the quality of our lives. As well as the benefits to health walking has potentially important environmental and social implications. It is also the least likely activity that is going to cause injury as we are designed to walk. Fossil records show that we have been walking (bi-pedal) for around 4 million years. That is a lot of walking and as time has progressed we have become better at it.

Walking is the most common and preferred activity for people, for example in the US 54% of women and 41% of men cite walking as their most common activity during the past month 1 and it as the most frequently reported physical activity among high school students 2. While it might be the major activity we just don’t do enough of it. In England, for example, 29% of adults do less than 30 min of moderate physical activity per week and about 8% do not even walk continuously for 5 min over 4 weeks 3

Just as important however is the speed of walking. Walking at a pace of 5–8 km/h expends sufficient energy to be classified as moderate intensity and is an easy and accessible way of meeting physical activity recommendations. Studies have also shown the speed of walking is important - in a meta-analysis of five studies (14,692 participants total), people in the slowest quarter of walking speed, had significantly higher mortality rates than did those in the fastest quarter 4, that is the faster walkers live longer. A very good reason to up the pace a bit. An average walk (not a stroll) is about 5.0 kilometres per hour (km/h) up to 6.5 or 7 km/h for a brisk walk.

Walking offers many benefits to health, whether it be preventing disease, contributing to emotional and cognitive health, or helping to maintain independence later in life. Walking is the real “wonder drug” that we all need to be taking. And while the benefits are multiple and the behavior is simple most of us don’t do enough of it. In effect the benefits of walking can been seen to outstrip all the potential for pharmaceutical drugs on the market place and in many cases walking can be seen as an alternative to conventional drug therapy. The health benefits and resulting medical care savings of walking and physical activity are extremely large. Further, these benefits accrue regardless of age, weight, or existing health challenges. In a study of institutionalized elderly women aged over 70 walking 50-65% of the maximum heartbeat had the effect of decreasing blood pressure together with improvement in flexibility, left hand grip strength, sense of equilibrium, self-esteem, depression and life satisfaction 5. People only need to be active for at least 150 minutes a week and it can occur in short bouts, lasting at least 10 minutes or longer periods if you like. But the more you walk, the faster and the bigger the steps you take the longer you live. No other activity shows up with so many benefits as walking.

Systematic reviews and meta-analyses have shown walking to have various and multiple health benefits including positive effects on fitness, fatness, blood pressure control, weight loss, depression and other areas of mental health and stress, and cardiovascular disease risk prevention, pain management and spinal support as well as some cancers such as colorectal cancer. A systematic review of walking found statistically significant reductions in body fat, BMI and blood pressure and increases in breathing capacity 6. The review reported a reduction in blood pressure of around 3.72 mm Hg, around the same lowering from most of the pharmaceutical drugs on the market. The greatest benefit was reported in those involved in group walking 6. This reduction is comparable to earlier large studies of walking and resting blood pressure 7 which found a 2% reduction in blood pressure from walking. The importance of this difference becomes significant when you know that a 2 mm Hg reduction in blood pressure can reduce coronary heart disease risk by 6% and stroke and trans-ischaemic attacks (transient strokes) by 15%. 8. While other studies have reported a reduction of only 2 mm Hg in blood pressure could reduce stroke mortality by 10% and mortality from vascular causes in a middle-aged population by 7%.

Walking has also been associated with a reduced risk and even playing a role in reversing type 2 diabetes. A Harvard University study examining the exercise habits of more than 70,000 women, showed that a 40 minute walk every day reduced type 2 diabetes risk by 40%, and with a longer walk the risk could be decreased by an even larger percentage. Even adults with Diabetes, those who walked for 2 or more hours a week lowered their mortality rate from all causes by 39 per cent. However, the timing of walking also appears to be important. Walking after a meal reduces the blood sugar and lipid levels by increasing their absorption into the muscles. Walking after a meal the sugar and lipids are directed into the muscles not to be added as fat around the liver. When you walk you use more than 200 different muscles which create healthy molecular signals which positively alter the body’s biochemistry and metabolism. One of these is a particular muscle chemical, lipoprotein lipase (LPL), a protein enzyme has been studied in depth because this enzyme has a central role in several aspects of lipid (fat) metabolism. LPL controls plasma triglyceride (fat) breakdown (burning the fat into energy), shifting the cholesterol from LDL to HDL and other metabolic risk factors decrease when we stand or begin walking. The importance of producing enough LPL cannot be underestimated as people who produce less LPL have a five-fold increase in the risk for death and greater chronic heart disease. The production of LPL is therefore extremely beneficial to us.

Regular walking is beneficial for enhancing mental health, for example, reducing physical symptoms and anxiety associated with even major stress. In a study of Post Traumatic Stress (PTSD) symptoms, depression, anxiety and stress, sleep quality,  in 76 participants age, 47 they found total PTSD symptoms, combined symptoms of depression, anxiety, and stress, and sleep behavior were significantly and negatively associated with total walking time and that increased PTSD symptoms were associated with lower levels of walking. 10. In a study of twenty healthy, elderly adults with a mean age 70, negative feeling scores such as tension-anxiety, anger-hostility, and confusion significantly improved after walking 11.

Depression is a common disorder worldwide widely recognized now to be an inflammatory condition and not one of a serotonin imbalance like the drug companies want you to think. Walking has been shown to alleviate depression. In a Meta-analyses using eight trials showed that walking has a statistically significant, large effect on symptoms of depression 12 and no negative side effects. In a study investigating the mood in 102 sedentary, ethnic minority women over a five-month period they found walking significant decreased depressive mood and an increase in walking over the course of the study was associated with change in vigor 13. One study of fifty breast cancer patients reported 12 weeks of moderate intensity walking mid-way through chemotherapy had positive effects on fatigue, self-esteem and mood. The study reported 80 % adherence rate to completing the 12-week intervention and recording weekly logs and reported the self-managed, home-based intervention was beneficial for improving psychosocial well-being 14

Walking has also been found to improve our brain development. Older adults, who walk frequently, have lower risk for cognitive decline in later life. In a study of 299 adults, aged 65 or older, greater levels of walking, predicted greater volumes of frontal, occipital, entorhinal, and hippocampal regions of the brain, 9 years later. Walking 72 blocks, was necessary to detect increased grey matter volume, but walking more than 72 blocks added additional brain volume. Additionally, greater grey matter volume with walking reduced the risk for cognitive impairment 2-fold. Greater amounts of walking were associated with greater grey matter volume, which is in turn associated with a reduced risk of cognitive impairment. These findings are in line with data that, aerobic activity induces a host of cellular cascades that could conceivably increase grey matter volume 15.

We now know that Alzheimer’s disease is a cardiovascular condition related to blood flow and nutrients reaching the brain. Epidemiological data support an inverse relationship between the amount of physical activity including walking undertaken and the risk of developing both Alzheimer’s and Parkinson’s disease 16,17. Beyond this preventive role, exercise may also slow down their progression 18,19. Several mechanisms have been suggested for explaining the benefits of physical activity and walking in the prevention of Alzheimer’s. Walking improves the efficiency of the capillary system and increases the oxygen supply to the brain, thus enhancing metabolic activity and oxygen intake in neurons, and increases neurotrophin levels and resistance to stress. Walking activates the release of neurotrophic (brain growth) factors and promotes the formation of new blood vessels, facilitating the generation of new neurons and synapses, which in turn improve memory and cognitive functions 20.

Research with Alzheimer's Disease subjects has shown that walking plus conversation has an even better preventive effect than walking alone 21, suggesting that the "socialization effect" of exercise is an important aspect. In another controlled exercise trial, the practice of walking combined with bright light exposure improved sleep among Alzheimer's Disease patients 22 suggesting that we should be doing more of our walking outside in the sun with our friends.

Other co-benefits of regular walking include improved academic and job performance and improved community cohesion. Creativity has a number of positive benefits. Studies have found gains in participants’ ideational fluency (creativity) after aerobic running or dancing 23, with similar results for aerobic walking, regardless of participants’ fitness history 24,25. Whether one is outdoors, or on a treadmill, walking improves the generation of novel yet appropriate ideas, and the effect even extends to when people sit down to do their creative work shortly after. A group of four separate experiments by the same research group showed walking boosts creative ideation in both real time, and shortly after each of the four experiment variations. In the first experiment it was shown that walking increased the creativity of 81% of participants. In the second experiment, an increase in creativity, was still seen when participants were seated after walking. Experiment 3, demonstrated that walking outside prompted the most novel and highly creative thinking, when compared to those sitting inside and out, and walking inside. Walking is believed to promote free flow of ideas, being a simple and robust solution to increasing both creativity and physical activity 25. Perhaps every workforce should add some walking time?

 “All truly great thoughts are conceived by walking.”- Friedrich Nietzsche (1889)

  1. Watson et al
  2. Song et al
  3. Farrell L, et al. 2013
  4. Murtagh et al., 2015
  5. Son and Lee. 2001
  6. Murphy et al 2007
  7. Kelley et al. 2001
  8. Cook et al. 1995
  9. Lewington et al 2002
  10. Rosenbaum et al 2016
  11. Erickson et al 2011
  12. Robertson R, et al. 2012
  13. Lee et al 1999
  14. Gokal et al 2015
  15. Erickson et al., 2010
  16. Alonso-Frech et al 2011;
  17. Norton S et al 2014
  18. Ahlskog 2011;
  19. Pitkälä et al. 2013
  20. Paillard et al 2015
  21. Tappen et al 2000
  22. McCurry et al 2011
  23. Gondola, 1986, 1987
  24. Netz, et al., 2007
  25. Oppezzo and Schwartz, 2014

 

 

 

 

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Why We Overeat?

Why We Overeat?

I had a friend a long time ago that used to seesaw with her weight many times over the year. Whenever she got depressed or upset she would eat a lot of rich, high calorie foods that gave her some instant pleasure. Her favourites were chocolate, and Milo by the spoonful, straight from the can. Despite her reasons for binge eating, it didn’t bring any happiness and in fact contributed significantly to her problem. We need to deal with the beliefs that underlie the undesirable eating patterns as part of any dietary program.

Examining emotions and habits during a weight loss journey gives an insight as to why people overeat or have a hard time maintaining weight after losing it. The reasons given for overeating and excess weight gain often have similar root causes including boredom, emotional instability, and stress. Some of these I have already covered but the potential list is pretty long.

The major reasons for overeating include and our appetite includes

  • Busyness
  • Time of day (energy levels)
  • Mood
  • Nervous
  • Stress
  • bored
  • low self esteem
  • hormonal
  • hunger
  • peer/social pressure
  • routine/habit
  • media and advertising
  • low price/convenient
  • mental stimulation
  • too busy
  • Feeling Unloved
  • Anxious or restless
  • Happy
  • Angry or jealous
  • Tired
  • Dissapointed or rejected
  • Depressed
  • Emotional
  • Availability

Or if there are real food cravings, it may require some mineral or nutritional supplementation. For example, some sugar cravings can be significantly reduced with chromium or vanadium supplementation. Sometimes more protein-rich foods need to be eaten.

Lets look at some of the main ones

Busyness and stress are often the underlying factors why we put on weight. One way or another it prevents us from doing what we need and know we should be doing. Too busy to exercise, to busy to eat right or buy the right food, too busy to take the time for ourselves, too busy. Woman are often so busy with looking after the family they constantly justify another little treat and poor eating to get them through another day. While both men and woman often become too busy around their careers. Taking a bit more time for ourselves and focusing on our health and healthy eating can make a big difference to our lives.

Emotional weight gain can be a major problem. Hence why any weight control program needs a lot of emotional support. To much weight on the mind can put on weight in the body. In a study of eating disorders in girls in the 7th to 10th grades, which also applies to us as we age, many of them reported an inability to distinguish between emotional feelings and hunger.  Some of these girls were unable to distinguish between scared, angry and hungry and are able to lump all of these conditions together, which leaves them to overeat whenever they have an emotional feeling.  This is no wonder if you look at how we use foods as rewards and distracters as we grow up. Often when we are feeling upset or anxious we use food as a substitute.

Energy lows can be a major appetite trigger, either directly or indirectly is the amount of energy you have. If you understand your daily energy cycles you can avoid many food cravings and not confuse your levels of energy with poor eating habits. Remember, they are just habits. Most binge eating for example occurs in the low energy times of late afternoon and late evening when energy levels are low. At this low energy time you are also more likely to feel in a low mood so the food further acts as an energy catalyst to get you out of that mood. Only the solution is only a short-term mood changer and often has a negative energy and emotional rebound effect. In support of this one study of dieters found that the average time at which relapse occurred was late afternoon at 4.34 pm, about 4 hours after their last meal when they were moderately hungry and their energy levels were low. The majority of cases for temptation and relapse were characterised by upset including anger and by depression or tiredness.

On the other side of the coin research is increasingly showing that how we feel is also affected by what we eat. Research shows links between depression and nutritional deficiencies.  The research also shows that the deficiencies do not have to be excessive to depress the mood. So it can become a vicious circle of food-mood-food. Dieting and food restriction can also play havoc with our moods. In a review of dieters the research concluded that negative moods particularly depression increased eating amongst the dieters. In another study of people who were at least 30% over-weight and ate only a fasting supplement of 420 calories per day over a 10 week period, they most commonly violated their diets in the second month at a time when they were feeling fatigued. Using brain imaging machine when you fast or deprive yourself of food (as in a diet), your brain sees high calorie foods as being far more pleasurable. The cravings and temptation to eat unhealthily, will be far more intense. This is what they found in the short term, at least. It appears The orbifrontal cortex is responsible for how the brain perceives the “value” of a food—or how pleasurable it will be to eat.

There is no doubt the negative effects of low moods and energy have on weight management. For many people when these two are low up goes the weight. Fortunately, for the majority of people, physical activity is the most effective way to raise energy and reduce tension. It produces rapid and reliable results that can change moods immediately. Overwhelming scientific evidence shows that even moderate physical activity has the ability to increase your energy, unlike the energy drinks which actually make you feel more drained. In an experiment where one group was exercising by walking and a control group sat quietly reading over materials there was a significant change in mood that was significant and unmistakable with the walking group. Research has highlighted that 15 minutes of walking produces slightly more energy than 5 minutes but even 5 minutes of brisk walking has a significant effect. After just a 10 minute brisk walk there were still statistically significant effects 60 minutes later and 120 minutes later a week energy increase was still evident. A brisk walk therefore energises the person for somewhere between 30 to 90 minutes afterward.

In a study on unhealthy snacking researchers identified six distinct motives for snaking including opportunity induced eating, coping with negative emotions, enjoying a special occasion, rewarding oneself, social pressure, and gaining energy. Sound familiar? While Enjoying a special occasion and opportunity induced eating were most important. For all reasons except to enjoy a special occasion, younger people reported a higher score. Women indicated a higher score than men on coping with negative emotions, enjoying a special occasion and gaining energy. People who diet to a stronger extent reported a higher score for snacking because of social pressure, to reward oneself and to cope with negative emotions, with the latter also being related to a higher BMI.

Other studies have also made a link between emotions and snacking. One study showed movie-goers watching tearjerkers ate between 28% and 55% more popcorn both in the lab and in a mall theatre. Previous studies have shown that humans who play violent video games show clear signs of distress (ie, negative stress), comprising higher blood pressure as well as reports of less fullness and a tendency to prefer sweet food. Studies suggest that watching scenes of an action movie may cause distress, a condition that can increase food intake in the absence of hunger. One study found action and adventure movies also lead television viewers to eat more calories – but only if the foods are within arm’s reach. With action movies, people seem to eat to the pace of the movie. In contrast, watching an engaging comedy clip has been linked with decreasing tiredness, sadness, irritation, anxiety, and restlessness, while increasing relaxation and joy. Thus, watching a comedy clip may cause eustress (ie, positive stress), which, owing to its high rewarding property, may reduce an individual’s concomitant drive to eat. While another study found that female students ate less grams when watching a comedy program compared with food intake when watching a television (TV) documentary.

Our eyes lie

Another major factor in overeating is the supersize me phenomena. Portion size is a key environmental driver of energy intake, and larger-than-appropriate portion sizes increase the risk of weight gain. Unfortunately the size of food packaging and portions has steadily increased over the past 30 years and these super sized food portions play a major role in weight gain. Simply people who sit down with bigger portion sizes of food are more likely to be overweight and obese while those who maintain a small portion size lower their weight. Whether it is from our parents telling us to eat all our food on the plate or our hunter-gatherer starvation mentality once it is on our plate we tend to eat it and as a result over eat. For instance, one study reported that 54% of American adults generally claim that they attempt to eat until they “clean their plates”. Interestingly very early studies showed this when participants who drank soup through a tube drank less when they had visual contact with the soup than when they did not. Literally a person's eyes may influence how much they consume, leading them to be less influenced by physiological cues of satiation. As a result, their estimate of how much they have consumed and how full they are may have to do more with what they believe they saw themselves eat and less with how much they actually ate. In a study of fifty-one men and women were served lunch of different portion sizes subjects consumed 30% more energy (676 kJ) when offered the largest portion than when offered the smallest portion. Larger portions led to greater energy intake regardless of serving method and subject characteristics. In one study after a 3 month intervention subjects who regulated their portion size had a greater weight change from baseline to the end of the 3-month intervention period loosing 3.7 kg compared to 0.1 kg in the control group showing that portion control is effective to reduce body weight in overweight and obese diabetic subjects.

It is time to have a think on why we overeat and puts some steps in place. Simple strategies like keeping a food mood diary can help you identify any common factors in overeating. While serving food on small plates can make a big difference to how much you eat each meal. Time to downsize our meal sizes.

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Stress and Sleep

Stress and Sleep

While many factors can contribute to insomnia and poor sleep undoubtedly the most important one in the twenty first century is stress. Increasing research shows that there is an activation of the stress-response system and the degree of sleep disturbance experienced correlates with the level of stress-response activation and that insomniacs and others with poor sleep patterns experience more psychological stress. Including scoring higher in a psychological distress survey and being more sensitive to stressful conditions.

Unfortunately there can be a vicious cycle of stress poor sleep and more stress. If you are not getting enough sleep, you have to rely more and more on your alarm clock, and if you oversleep and wake up already fatigued.

The stress response stimulates production of many chemicals which elevate blood glucose levels, raise heart rate, and alter the secretion of cortisol which makes it hard to relax enough to sleep restfully, and without enough rest, the body will not be able to readjust to a normal circadian rhythm, prolonging the cycle of feeling stressed and restless.

In a study using fifty-three women with insomnia (and seventy-eight controls), insomniacs had higher levels of urinary morning cortisol and also scored significantly higher on a psychological distress questionnaire than did the controls. A similar study found the insomniac group slept for a shorter amount of time under high-stress conditions than under low-stress conditions, while the normal sleeper group showed no variation across conditions.

In another study although all subjects reported equivalent numbers of daily stressful events, people with insomnia found the impacts of these events to be more severe. Insomniacs also experienced major life events more intensely, were much more alert before bedtime, viewed their lives as more stressful, and used emotionally-based coping strategies to deal with stress more often than did the normal sleeper group. The study concluded that the way insomniacs perceive and process stressful events as being beyond their control was perpetuating their insomnia. It appears that although normal sleepers and insomniacs experience similar types of stressful inputs in insomniacs the stress-response is more sensitive to these inputs and its activation leads to lack of sleep.

 

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The Drawbacks of Cooking

The Drawbacks of Cooking

Cooking and processing food is something that is widely accepted, but many of us don't realise that there may be nutritional drawbacks. High heat, as well as many of the cooking processes, alters the physical and chemical structure of food, changing how it is digested and the nutrients that are available to be absorbed. Enzymes are destroyed and nutrients can be lost from almost all forms of cooking, depending upon the type of cooking, temperature, pH, oxygen content and type of food. In addition, the processing of foods may add toxins, which can build up in the body, causing a negative effect on health.

Vegetables, provide a good example of how cooking reduces the amount of valuable nutrients. With vegetables, cooking by means of boiling or steaming produces three composition-changing actions: shrinkage due to the extrusion of vegetable juices; leaching by either boiling water or condensed steam; and hydration.

Leaching produces a higher loss of water-soluble nutrients in vegetables, which increases with duration of boiling and the quantity of water used. Between 70 and 80% of vitamins and minerals including vitamin C and B group (such as thiamine and folate), and potassium are lost during the boiling process. Steaming vegetables does not result in the loss of anywhere near as many nutrients into the water as with boiling; however steamed vegetables still may lose up to 30% of their water and water-soluble nutrients. As the nutrients leach into the cooking liquid, that full value of the vegetable can only be maintained, if this is consumed as well as the solid food.

In experiments, the boiling of spinach and broccoli removed between 51% and 56% of folate. Thiamine (B1) has one of the highest losses by cooking—up to 80% with complete loss from oven-roasted food, while boiled legumes had 50% thiamine loss. Riboflavin (B2) losses tend to be less but still significant; roast chicken retained only 22% of its riboflavin after cooking.

The fat-soluble vitamins, A, D, E and K, are not lost whilst boiling, because they are not water-soluble, though they are still prone to oxidation damage, through high heat. However, other cooking processes can certainly have a big impact on the levels of the fat-soluble vitamins. Oven roasting lamb chops decreased the vitamin A content by 58%. Similarly, baking fish reduced vitamin A content by 37%. Many foods lose between 19 and 57% of the carotenoids, beta-carotene and xanthophylls when cooked.

The minerals that form the most soluble salts, potassium and sodium, have the highest loss using wet (boiling and streaming) cooking methods. In an experiment, boiled fish lost 25% of its potassium and 60% of its sodium. Pressure-cooking resulted in losses of 51% of sodium and 71% of potassium in mangrove seeds. Boiling of some vegetables (mushrooms and asparagus) reduces their selenium content by between 29% and 44%.

Protein loss through cooking, is minimal, appearing to be around 13%. However, after cooking, proteins become harder to digest as they form cross-links with reducing sugars, meaning the body has to work harder to break down, which may lead to the fermentation of raw meat in the digestive system. Raw meat, such as steak tartare and sushi, are much easier to digest, although they are an acquired taste. 

Cooking increases acidosis

Cooking food, alters its natural state, and therefore the way it interacts with the body. Ideally the body should have a neutral pH level, around 7.2 to 7.4, but heavily processed foods and cooked animal proteins can increase the acidity of the body. As a result acidosis (increased acid in the body) decreases the body’s ability to absorb minerals and other nutrients, energy production in the cells and the body’s ability to repair damaged cells.

Heat produced toxic compounds

The higher the cooking temperature, the more food is altered, sometimes into toxic compounds. One study found close to 3,800 heat-formed chemicals in cooked food, including a number of carcinogens. Toxins developed from cooked and processed foods include acrylamide, heterocyclic amines, nitrosamines and polycyclic aromatic hydrocarbons (PAH’s). These substances are all carcinogens. Carcinogens such as acrylamide, which is found in cooked and processed foods, are not found in raw foods. PAH’s, the burnt bits of food (for example, from barbequeing meat or toast), are known to be carcinogenic and are the oldest known chemical carcinogens. In food, more than 10 out of 20 PAH identified have been shown to be carcinogenic in experimental animals. Oral administration at various concentrations in rodents have resulted in stomach, ovarian, lymphoid, mammary and hepatic tumours. The major sources for PAH in food is during heat processing (grilling, smoking, toasting). The formation of PAH is minimal below 400oC, however the amounts increase linearly in the range 400-1000oC or when foods are in direct contact with flames. Smoking also forms a variety of other toxic compounds including nitrogen oxides which can form nitrites and are able to react with amines and amides, yielding N-nitroso compounds (Nitrosamines and Nitrosamides). Formation of these compounds occurs optimally around pH 3.5 and is catalysed by high temperatures. A significant portion of nitrosamines produced during the frying of food is also found in condensed vapours and may be breathed in by people doing the cooking. These nitroso compounds are well known cancer causing chemicals in both human and animal studies.

Various mutagenicity (pre cancer cells) tests also showed positive results related to amino acid pyrolysis (protein cooking) products and are considered potent liver carcinogens in rats and mice. Frying at 143oC for 20 minutes only produced low activity, whereas 191oC and 210oC for up to 10 minutes gave much higher mutagen activities. In meat it appears that only low levels of TA98 mutagenic activity are produced when ground beef is microwaved, stewed, simmered, boiled or deep fat fried. Baking, roasting and broiling produce moderate activity, while frying produces the highest activity.

Increases in time and temperature of cooking have been shown to increase advanced glycation end products (AGEs), which are shown to increase inflammation, particularly in diabetics. AGE products do considerable damage in the circulatory system and are increasingly associated with a range of adverse health effects from which diabetics suffer, including those leading to gangrene and blindness.

Plastics in heating, cooking and Microwaves

Unfortunately a lot of people do not realise that plastics leach out toxic substances in the food and the rates of this release is often dependent on heating and the type of food. So putting hot food into plastic containers or heating food in plastic containers, which is common with microwave cooking, increases the release of different toxic plastic compounds such as PVC, BPA (Bisphenol A) and plasticizers like and phthalates (DEHA).

DEHA is a phthalate like chemical added to plastics to make them more pliable is a known endocrine (hormone) disruptor and causes testicular and reproductive defects in rats. In studies conducted on rats, DEHA has been known to cause androgenic effects. It was also found to have caused developmental toxicity in rat foetuses.

BPA has been found to cause oestrogenic effects in rats in low exposure, a change in maternal instinct in rats at one fifth the level considered safe and that it causes aneuploidy (extra or missing chromosones) in mice. Aneuploidy is the cause of spontaneous miscarriage in humans, and causes between 10 and 20 percent of birth defects, including Down's syndrome. This implicates BPA in a suite of health problems.

“Microwave safe” is not a health claim and has no bearing on the movement of chemicals into the food. Instead it is a warning that the plastic will not physically deteriorate if exposed to microwaves. That is it will not melt. Many of the microwave safe products use polyethylene instead of other plastics such as PVC as polyethylene has no plasticizers. PVC is a known liver cancer causing agent.

A common piece of cookware in most kitchens, teflon cookware is a high temperature cookware that is made with material that enable’s it to heat consistently at a lower temperature to prevent burning, and is more resistant to damage caused by sudden temperature changes, and maintains a non-stick surface. Teflon cookware is formulated from Polytetrafluoroethylene (PTFE) and Perfluorooctanoic acid (POFA), both being toxic substance which are released into the food and into the air.

Cooking with Teflon enables these gases to be released and penetrate the alveoli creating respiratory problems, causes direct damage to cell membranes of the lungs, elevates cholinesterase activity and increases levels of inorganic fluorides in the human body. Although research on the effects of PTFE on human health is limited, extensive animal studies have shown inhalation exposure to produce adverse health effects in several organs and at higher concentrations even death. Rats exposed to high concentrations developed hemorrhages, edema, fibrin deposition in lungs and damage to the proximal tubule of the kidney. Most alarming however, PTFE releases toxic pyrolysis products in the air that can cause rapid death of birds. Exposure of budgerigars to PTFE pyrolysis products in the air for only 9 minutes produced severe clinical signs, lesions and death of 31 of 32 birds. A similar effect on five cockatiels was also observed in an incident where all five had died within 30 minutes of exposure to an over-heated frying pan containing PTFE.

Of additional concern to the manufacturing of Teflon cookware is the inclusion of Perfluorooctanoic acid (PFOA) in its’ non-stick coating. Perfluorooctanoic acid is linked to damaging the human immune system, altering the endocrine system, causing infertility, damaging children’s health and producing development problems, and to be carcinogenic. One study found PFOA production workers in the U.S. have a three-fold increase in developing prostate cancer. The U.S. EPA state that not only is PFOA a likely cancer carcinogenic, exposure to the chemical also impairs the fertility of women. While exposure to PFOA in utero (to the fetus) has been linked with reductions in newborn birth weight and adverse effects on the skeletal and organ development of the baby. Exposure to POFA from Teflon cookware alters the endocrine system including decreased levels of reproductive hormones and disrupted thyroid hormone regulation.

Other than the emissions from Teflon cookware into the air lesser known side effect of cooking is the creation of indoor combustion air pollutants. Carbon monoxide (CO), nitrogen dioxide (NO2), and particulate matter (PM) are harmful air pollutants that pose significant short- and long-term health risks. These same pollutants are also some of the most common contributors to unhealthy air inside homes, due in part to cooking. Researchers now understand that the process of cooking food and even simply operating stoves—particularly gas appliances—can emit a cocktail of potentially hazardous chemicals and compounds. Within our homes, these pollutants are less diluted than they are outdoors, and in the absence of proper ventilation, they often are trapped inside. Literally millions of people are routinely being exposed to air pollutants at levels that we don’t allow outdoors

Cooking and Weight gain

Cooking is a universal human behaviour that has been proposed to function partly as a mechanism for increasing dietary net energy gain and Research shows that cooked foods are a major contributing factor to the epidemic weight gain and obesity crisis we see now. A long time ago farmers found out that animals eating raw food put on a lot of lean mass but not much fat or the weight needed to make good profits. So farmers started processing the food to get bigger weight gains. On experiments feeding mice processed grains put on significantly more weight and became obese compared to mice fed whole grains in their natural unprocessed form.

An explanation for this is that processing and cooking increases the energy gained from carbohydrate, protein and fat sources. In fats the cellular structure of many foods constrains their digestibility. For example, Oilseeds have cell walls composed mainly of indigestible non-starch polysaccharides and store their lipids in oil bodies, intracellular, spherical organelles coated by oleosin proteins. These features hinder digestive lipases from accessing the encapsulated lipids which may explain why unprocessed (raw/whole; RW) nuts and other oilseeds have high measured lipid and energy content, but display lower digestibility. Cooking and/or mechanical processing tears cell walls and disrupts oil bodies, promoting lipid release which shows that processing could increase lipid digestibility, because, unguarded by cell walls and oleosins, the freed lipids are likely more accessible to lipases.

Prebiotics through the metabolism of the gut microbiome have also been linked to satiety effects and foods that contain fiber, protein, and plant-based fat tend to be the most filling. These nutrients slow down digestion and the absorption of nutrients, a process that helps you feel physically full for longer, and also means lower blood sugar and insulin spikes. While all unprocessed plant sources are rich in prebiotics leeks are rich in fructan and cellulose fibers (types of prebiotics) are long enough to survive all the way down the GI tract. However, cooking shortens the fiber chain, so it should be eaten raw or lightly cooked.

 

 

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Exercise for Weight Loss

Exercise for Weight Loss

Exercises on television shows like “the biggest losers“ give a false impression of the role of exercise. Exercise, unless it is extreme in the case of the biggest losers who have cameras and personal trainers and doctors etc. plays a relatively lesser role in weight loss and may even backfire in people who over do it. That doesn’t mean you don’t do anything because being active is critical for many aspects of your overall health and wellbeing were just saying you don’t have to be a gym junkie to get to your optimal weight. A lot of evidence shows that aerobic exercises which are great for the heart are minimally effective for weight loss, although they have multiple other benefits including reducing your risk of all forms of chronic illness. The problem is that, in general terms, exercise does not burn tons of calories (unless we’re doing heroic amounts of it). It doesn’t usually take much additional eating to wipe out any calorie deficit induced through exercise. For example the energy burned while walking 30 minutes (170 calories) each day will only lose you around one kilogram after 50 days. In the study, 23 overweight and healthy men engaged in a 6-month programme of exercise 108 minutes of exercise a week changed the expression of about a third of the genes in the fat cells, including some that relate to the risk of type 2 diabetes and the development of obesity. As well as changes in waist circumference, waist-to-hip ratio, diastolic blood pressure (the lower of the two blood pressure readings), resting heart rate and levels of HDL-cholesterol. However, weight only declined by 1 kg on average and appeared to be no less fat for their efforts.

In a meta analysis of children’s weight loss, Physical activity interventions were not associated with reductions of BMI. However, there was an association between the interventions and reduction of blood pressure. In a study of overweight people expending either 300 or 600 calories a day exercising for 12 weeks twice the exercise did not translate into improved weight loss. Those doing 300 calories of exercise lost an average of 2.7 kg compared to 3.6 kg for the 600 calorie exercise group. Double the exercise lead to a 30% extra loss of weight. Of interest those exercising for about half an hour a day (300 calories) had a more positive attitude to exercise. Doing larger amounts of exercise are harder which is a barrier to maintaining the exercise.

On the positive side exercise is great for keeping weight off. The more you are active the less likely you are to put on excess weight. In a study of 25 639 men and women an increase in weight was associated with higher risk of being inactive 10 years later. Compared with stable weight, a gain in weight of more than 2 kg per year is associated with physical inactivity 

Exercising for weight loss

But don’t stop exercising if you like exercising just yet because the level of exercise also has a large impact on your Resting Metabolic Rate and thermogenesis. There are certain things you can do to improve your weight through exercise. The first is to increase your muscle mass through anaerobic, muscle building exercise. The more muscle you have the higher your resting metabolic rate. That is the more you burn excess fuel while you are resting

You can also use exercise and physical activity to increase your thermogensis at critical times, in a sense tricking you body into burning calories before it is stored around your waist. Insulin is a major contributor to weight gain. The more insulin released with a carbohydrate dense meal the more weight you put on around the waste. However, increasing physical activity soon after a meal, even just standing up increases the cells requirements for the sugar without releasing extra insulin. Within seconds of any physical activity one of the non-insulin sugar pathways into the cells, the Glut 4 transporters are activated to remove sugar from the blood. This reduces blood glucose levels and improves insulin sensitivity (very good for diabetics). That is less insulin does more work. Regular exercise also increases the number of Glut 4 transporters. The more you exercise the more Glut 4 transporters your body will make. Any diabetic will tell you that as soon as they exercise their blood sugar levels goes down straight away. This means less to be stored as fat around the waist. In a study of thirteen obese-patients with type-2 diabetes post-dinner resistance exercise improved both postprandial glucose and glycation-end products, the damage caused by sugar. Post meal physical activity takes the sugar out of the blood before it can cause harm and build up around the waist. Associated with the increase in Glut 4 transporters is that exercise also increases the production of mitochondria which are the energy burning factories of the cells, and a lack of exercise causes numbers to deteriorate.

Exercise for your hunger genes

Like the different foods exercise can also alter how hungry you feel. In its natural environment your body is in perfect balance and everything feeds back on itself to constantly bring it back into balance. While being more active and exercising generally sends messages to eat more, to keep it all in balance you can also use exercises to suppress your appetite and trick the body. Exercise can suppress appetite, subsequent energy intake, and alter appetite-regulating hormones for a period of time post-exercise. Most people experience appetite suppression following an acute bout of exercise as exercise reduces your immediate feelings of hunger. In a study of 9 women who had fasted for some time before the experiment. They found that appetite ratings of the subjects in the exercise group fell for up to 2 hours after they had been placed on a treadmill for 30 minutes. Similar results have been found with different types of workouts and generally the exercise with greater metabolic and mechanical demand (weight-bearing exercise) showed greater immediate appetite suppression. So if you are reducing your calorie intake it is worth being active before a meal as well to reduce those immediate hunger pangs.

There is just no down side to physical activity unless you try to do too much too quickly like the biggest losers.

Standing up for weight loss

Sitting for any length of time may not be good for us, as more and more evidence shows that sedentary behaviours including sitting, watching television, using a computer, and driving a car are risk factors, independent of physical activity, for adverse chronic disease in adults such as obesity, diabetes, heart disease and much more. You can do a long run every night, but if you sit too long during the day you still increase your risk of these chronic conditions. In a study of 2,761 women and 2,103 men without clinically diagnosed diabetes, sitting time was detrimentally associated with waist circumference, BMI (body mass index), weight gain, blood pressure, fasting blood fats, HDL cholesterol, two-hour postload plasma glucose, and fasting insulin. A sure way to put on weight. In a meta-analysis using 48 studies, a consistent relationship of sedentary behaviour with mortality was found with weight gain from childhood. That is, the greater the sedentary time in childhood, the greater the weight gain.

It appears that any type of brief, yet frequent, muscular contraction throughout the day—such as standing or moving—may create healthy epigenetic signals which positively alter the body’s biochemistry and metabolism. One of these is a particular muscle chemicals, lipoprotein lipase (LPL), a protein enzyme has been studied in depth because this enzyme has a central role in several aspects of fat metabolism. Experimentally reducing movement by sitting had a much greater negative effect on LPL regulation than a positive effect of adding vigorous exercise training on top of the normal level of non exercise activity. In rat studies the amount of time spent sedentary influences how our bodies process fats given that leg muscles only produce the lipase lipoprotein (LPL) fat-processing molecule when they are being actively flexed, either standing or moving. What this shows is that by simply standing up more frequently you increase your muscle activity to reduce sugar and fats in the blood. To achieve even better effects you can stand up after a meal rather than sitting down and watching Television. In support of this one study reported that independent of total sedentary time and moderate-to-vigorous intensity activity time, increased breaks in sedentary time were beneficially associated with waist circumference, body mass index, triglycerides, and 2-hour plasma glucose. While in a study of 70 adults involving sitting for nine hours, regular activity breaks lowered plasma insulin levels and lowered plasma glucose when compared with prolonged sitting, even when compared with physical activity. While physical activity lowered plasma triglyceride more with regular activity breaks, activity breaks were more effective than continuous physical activity at decreasing negative blood sugar and insulin levels in healthy, normal-weight adults.

Overall, there is a compelling case for sitting reduction to be included in clinical preventive advice as a key component of “active living,” where adults and children are encouraged to “stand up, move more and sit less” across different settings and locations throughout the day. Just standing up every 20 or 30 minutes can have a remarkable health benefit reducing your risk of many chronic illnesses. How simple is that. The results of these studies suggest that, at a minimum, we need to be breaking up our sitting time every 20 to 30 minutes.

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Dangerous Beauty?

Dangerous Beauty?

For the last 50 years we have been brainwashed into thinking we need to apply more and more chemicals onto our skin and hair to make us look healthier and younger without even a second thought for what those chemicals are and they are really doing to us. In today’s technological advancements the increased use of chemicals in our homes and environment is out of control.

The majority of consumers are not concerned with the ingredients they are using, they trust the Governments who they think carefully regulate these chemicals and the manufacturers and the suppliers to provide safe products or they simply do not recognise the chemical substances written on the labels. Public awareness about the potentially harmful formulations of cosmetics is very poor

While the cosmetic industry and other funded agencies continue to justify using chemicals that potentially cause adverse health effects by stating these are at significantly low levels and do not pose a threat to human health and Consumers are led to believe the ingredients have been adequately tested and safe for use. In reality, most of the chemicals that are in these have been barely tested and the magnitude of their potential adverse effects is unknown. And this is without mentioning the increasing occurrence of asthma or our increasing affliction with twentieth-century diseases: multiple chemical sensitivity, auto-immune disorders such as chronic fatigue syndrome and allergies. These questions will not be answered for a very long time, as the study of toxic substances is still in its infancy. It relies on the crude method of using test animals and extrapolating these results to humans. Even if we could do all the tests we needed, it would take us hundreds of years and unimaginable amounts of money just to carry out the testing we do at present, on existing chemicals.

Many of the ingredients used in these products are also industrial chemicals, solvents and petroleum by‑products which have safety warnings about their use and exposure. It is not just the chemicals of concern but we are using more and more of these products, from an earlier age and for a longer period of time. With each successive generation exposed to the media we apply more chemicals more times than ever before in human history.

Our exposure to personal care products and cosmetics continues to increase each year. According to the Environmental Working Group, woman will have around 185 chemicals on her skin daily, and a man will have around 85. A study on how much we use these products found today's usage of personal care products and cosmetics around 6 times more than in 1983 and it is likely to be even higher now. The average woman now uses around 12 cosmetics and up to 25 different products, with more than 25% of women using 15 or more a day exposing themselves to more than hundreds of different chemicals every day. While the average male uses half this. The study found for example that liquid foundation is applied daily by 68.7% ‑ 74.8% of woman and 23.4% of woman applied the product twice a day on a daily basis. 65.3% ‑ 82.9% of people use shampoo daily and 26.6% use it twice a day.

Right now, research shows that these products can be produced with lower and lower toxicity. They can also be designed to work - to have real benefits without causing harm. In fact, some manufacturers are already committed to these principles. Buy safer products or stop buying hazardous ones. This may force the big multi-nationals to respond by manufacturing with safer ingredients, gradually removing the most toxic; but only if we, the consumers, use our market pressure, and take our money elsewhere. Ironically, we hold the ultimate power. Knowledge, and positive action based on that knowledge, is the way towards creating the changes we want. I did my PhD on formaldehyde exposure in the early 1990’s. It was clear then that this chemical caused a lot of problems and caused cancer in animals and probably humans. It was not until around 2013 that most of the big manufacturers said that they were now going to remove this chemical more than 20 years too late. In large, this can be attributed to the self-regulating nature of the cosmetic industry and the inadequate government regulatory bodies to protect the welfare of consumers.

The cosmetic industry is one of the largest and most profitable enterprises around the world generating large profits. Despite economic difficulties in the world, profitability of the cosmetic industry has been steadily increasing by about 5% each year and it has been predicted that this trend will continue into the future. Cosmetics and personal care products have become an essential part of the daily grooming routine of millions of people around the world. Personal care products are a 40 billion dollar industry in the United States, and worldwide worth more than $200 billion each year and increasing. This success can be explained by the use of powerful marketing techniques to influence the general public into buying cosmetic products. The cosmetic industry has played a significant role in shaping and reinforcing societal perceptions of physical appearance and personal hygiene. As a multibillion dollar industry, companies’ fork out massive expenditures on advertising, harping on the idea that one must be image conscious, and thus continue to consume cosmetic products. The modern market for personal care products is all-inclusive from females to males, from infancy to old age. With the ubiquitous availability of products that come in an overwhelming amount of different types, indulging in cosmetics has become a necessity, or so we are led to believe by the industry.

Unfortunately, with so much money and profits at stake the cosmetic and personal care industry is not without its greed and lack of scruples. To highlight this In September 10, 1997 hearings on the FDA reform bill (HR 1411), Senator Edward M. Kennedy stated: "The cosmetic industry has borrowed a page from the playbook of the tobacco industry by putting profits ahead of public health." Consumers are generally misled by advertising campaigns and fancy packaging as to what chemicals are contained in their skin care products. Many ingredients are promoted to improve the condition of the skin whilst their harmful effects are omitted.

The regulators whose job it is to protect our health play down the actual and possible effects of cosmetics and personal care products as they have to tow the bureaucratic line. They may acknowledge that some people react to chemicals in products and that the numbers affected are probably increasing. They may also acknowledge that some of the ingredients ‘might be toxic’. The regulator’s position is that these chemicals are safe until it is proven that they are doing harm. This extraordinary position has failed people who are already seriously ill and will continue to protect the manufacturer, not the consumer.

 

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Conscious Living Nutrition

Conscious Living Nutrition

Despite the overwhelming importance diet and nutrition have in our lives, most people show very little interest in food other than satisfying their hunger or taste buds. Perhaps this is because people are too busy doing other things, perhaps it’s too complicated or maybe it’s because of all the conflicting information ‘out there’. For many people it’s simply too confusing, and this confusion is brought about in part by the vested interests of those companies marketing our food stuffs.
 
To make their products competitive, the cheapest ingredients available are usually used, whether they are sources locally or internationally. Unfortunately, energy-dense grains, fats and sweets represent the lowest-cost dietary options to the consumer. Good taste, high convenience, and the low cost of energy-dense, in conjunction with larger portion options and low satiating power, are the principal reasons for overeating and weight gain.
 
The breakfast food people tell us to buy their product so that we’ll be eating a nutritionally balanced breakfast, but most of the nutrition in their products comes from the vitamins and minerals they add. The soya food industry and dairy industry tell us their products are healthy for a whole other set of reasons and the confusion deepens. This is complicated by the fact that we (including many doctors) usually have a poor understanding of even the basics of nutrition. Most people receive their information from the advertisements on television and from the food packets. It’s literally in our faces all the time, from when we first get up and stare at the breakfast food packaging, to the multitude of ads on television.
 
For the past 50 years we have had misleading information and as a result the public are confused about what they should be eating to stay healthy. Even people who spend their time trying to keep up with the information are confused. If you followed the recommendations on the food pyramid for the past 20 years there is a very good chance that you would have ended up with diabetes, had a heart attack or stroke, gotten cancer or had some other major chronic illness. Hence the high levels of chronic illness now experienced in developed countries. Even the new version, MyPlate, while a little easier to understand, will still increase your risk of chronic illness.
 
The food pyramid, which was developed in 1992 by advertising and marketing researchers to develop an image the consumer could identify with and easily understand. It was never intended to be a health guideline it was developed to sell agricultural produce. The pyramid was then widely distributed and has been used as an educational tool, basis for dietary assessment, and part of policy documents. To highlight the strong influence of industry on US food guidelines, in 2011 the US Department of Agriculture, the same organisation who created the food pyramid, labelled pizza as a vegetable because it has tomato paste. Any wonder the food pyramid was so wrong.
 
Most food guidelines are controlled by vested interests seeking only short-term gains through promoting nutritionally undesirable eating habits. For example, Nutrition Australia, the controlling body of the healthy food pyramid, has a number of corporate members, such as Dairy Australia, an industry group, as well as the company Tefal (which sells the number one deep fryer in the world). These corporate members may influence decisions made within Nutrition Australia. There are examples of the sugar and salt industry manipulating food guidelines and even protesting against claims of adverse health effects of their products; the main reason for this is protection of profits. Thus questions must be asked about the effects that these corporate members have on changes to the healthy food pyramid. If changes occurred would they work in favour of the corporate members or would they work in favour of human health?
 
Industry can manipulate food guidelines by using them as marketing tools. The Heart Foundation Tick (HFT), a common food logo, has guidelines developed by the Australian Heart Foundation. However, the HFT is a voluntary system having a minimum fee of $3,000, meaning food companies purchase the HFT after passing its guidelines, although the HFT can be placed on fruit and vegetables for free. As the HFT is voluntary it may not represent the best choice for the consumer; for instance a competitor’s product may be more nutritious but if the company has not paid for the HFT it is not endorsed by the Heart Foundation. Yet less nutritious products can be endorsed. The American version of the HFT, the HeartGuide Food Endorsement Program, lasted just two months with consumers, nutritionists and even the U.S. government rejecting the system as biased. Similarly, both the Canadian and British heart associations dropped their food endorsement programs to remain independent, leaving Australia one of the only countries maintaining the HFT. Recently the Heart Foundation Tick was given to a number of McDonald’s products as well as 48 sugary breakfast foods. The foundation seems to have not seen the growing body of literature on sugar and chronic illness, including heart attack, or maybe it did and simply ignored it. It should also be noted that the Heart Foundation has received millions of dollars from drug companies who have a vested interest in heart disease. Not so independent. Amongst many donations the drug company Pfizer made to supposedly independent health advocacy groups in Australia were $227,409 in 2008 and $126,000 in 2009 to the Heart Foundation. So much for independent heart health advice.
 
Perhaps the best example of industry’s vested interests is food claims upon products. Claims such as “low in fat,” “all natural” or “light” can often be misleading and trick consumers into buying something they think is healthy when it may not be. Industry suggests these claims are a source of information for consumers; however, these claims are often only a marketing tool influencing consumers, not a health promotion strategy. If the packaging on a food product makes a nutritional claim, it may be best not to eat that food.
 
If you search in the scientific literature for foods that improve your health, that is, foods which reduce the risk of diseases and give long term benefits, you’ll discover that fruits, vegetables, beans, nuts and seeds (and many vitamin, mineral and other supplements) are the healthiest and most nutritious of all foods. Most of the grains we consume are over processed carbohydrates with so little nutritional value that the food companies are forced to add vitamin and minerals to make them a little healthy. These foods also have a high glycemic index, which means they raise blood sugar levels very quickly, damages the blood cells and is converted to fat.
 
Everything you eat will either accelerate illness, or will work to health, strength and vitality. An excess of processed, grain-based food is debilitating to your body, as are all the over-processed foods. This and other dietary issues have been clouded by the focus on calories. Despite the obsession with calculating the energy units in food, the general population continues to put on weight and get sick from diet-related diseases. Instead our focus should be on the nutritional content of food, not on calories.

 

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Dark Chocolate Is Good For Exercise Intensity

Dark Chocolate Is Good For Exercise Intensity

Next time you want to go for a workout, or maybe just want to lower your blood pressure maybe you should consider a block of dark chocolate. Dark chocolate is abundant in flavanols which have been reported to increase the bioavailability and bioactivity of nitric oxide (NO). Increasing NO bioavailability has often demonstrated reduced oxygen cost and performance enhancement during submaximal exercise.

In this study of 9 cyclists Dark chocolate increased an number of measures to show improved performance including established gas exchange threshold (GET) and a two-minute time-trial (TT) as well as V.O2max by 6% .

Of late dietary supplementation with sodium nitrate or nitrate rich beetroot juice has become increasingly popular and has consistently been shown to reduce oxygen demands during submaximal exercise and resting blood pressure (BP). Recent studies have shown similar vascular improvements in NO levels from consumption of dark chocolate (DC) and previous studies have shown benefits in improving and lowering blood pressure in both normal and hypertensive patients. One study also reported reduced blood pressure from consumption of dark chocolate in overweight participants, demonstrating DC may decrease cardiovascular risk and enhance the cardiovascular benefits of moderate intensity exercise in at-risk individuals.

 

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BPA linked with obesity in children (again)

BPA linked with obesity in children (again)

Another study adds to evidence that environmental chemicals can contribute to obesity. The study examined prenatal and early childhood exposure to BPA and found children at 7 years of age put on significant more weight if there mother was exposed to BPA. However, the researchers did not see an association between body fat and BPA levels in the children at ages three or five. The researchers suggest that this may be a time of heightened vulnerability to the chemical.

The results of this study suggest that prenatal BPA exposure may contribute to developmental origins of adiposity and findings are consistent with several prior studies, raising concern about the pervasiveness of BPA. Other human studies have found a similar link between BPA exposure and signs of child obesity. BPA has been shown to alter the body’s metabolism, increasing weight gain and making it difficult to lose weight. In a study of 1,326 children, girls between ages 9 and 12 with high BPA levels had double the risk of being obese than girls with low BPA levels, validating previous animal and human studies. The chemical can alter the body’s metabolism and make it harder to lose weight. Girls with high levels of BPA, two micrograms per litre or more, were twice as likely to be obese as girls with lower levels of BPA in the same age group. Girls with very high levels of BPA, more than 10 micrograms per litre, were five times more likely to be obese, the study showed.

Animal studies have found prenatal BPA exposure linked to offspring obesity. When pregnant rats are exposed to BPA it increased the fat mass in offspring, even later in life. In animal experiments, a mother’s exposure to BPA is produced the same outcomes that we see in humans born light at birth: an increase in abdominal fat and glucose intolerance. However, BPA affects rodent fat cells at very low doses, 1,000 times below the dose that regulatory agencies presume causes no effect in humans.

BPA, a common plastic additive, can leach out of can linings and into the food and studies show that just about everyone has traces of the chemical in their body. Ninety-four percent of the women in this study had BPA in their urine.

http://ehp.niehs.nih.gov/ehp205/

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Parabens

Parabens

Parabens are one of the most widely and heavily used antimicrobial preservatives, which until recently, were found in up to 99% of cosmetics and toiletries. Typically, more than one paraben is used in a single product and they are often used in combination with other chemical preservatives and are commonly used in facial moisturisers, lipsticks, eye‑shadow and mascara, body sprays, deodorants, hair removal creams, shaving gels, body lotions, face creams, sunscreens, toothpastes, cleansers and shampoos. It is probably easier to say what they are not found in.

Unfortunately, multiple studies have also identified parabens in most of the personal care and cosmetic products analysed even if they were not mentioned on the label. In a study of personal care products methyl paraben was detected most frequently and at the highest concentrations. The highest concentration was in an “alternative” sunscreen. Of the 11 conventional samples with detectable parabens, 10 included products with “paraben” on the label. Nevertheless, in “alternative” products, the study found parabens in 7 products, including 3 sunscreens, that did not list parabens on the label. One study of the 215 common cosmetic products tested 93% contained parabens. Not only are they not be listing parabens on the label but manufactures may hide the chemical under the word ‘fragrance’, a collective term which covers over two thousand chemicals (Williams, 2004) or as the research shows they may not even label them as ingredients.

Parabens can be absorbed through application on the skin and able to enter the blood based on their fat loving (lipophilic) properties. As the vast majority of cosmetic products containing parabens are usually applied to the skin, it can be a major source of exposure. Average exposure to parabens is estimated to be around 76 mg per day which includes 1 mg daily from food, 50 mg from cosmetics and 25 mg from pharmaceuticals. Between 20 and 50 times more is taken in through the skin than food. As a result, extensive distribution of parabens in human samples, including milk, urine, semen, breast tissue and blood, has been reported over the past decade and widespread studies have now shown 2 or 3 or more paraben in 99% of the general population in many countries around the world.

Paraben absorption can also be enhanced by the presence of other chemicals such as ethanol, menthol and propylene glycol, which occur in a many commonly used cosmetic products Because parabens tend to accumulate they can be found in elevated concentrations in some tissues. In one study after eight hours of contact with skin 60% of methylparaben, 40% of ethylparaben and 20% of propylparaben were found to have permeated across the skins surface.

A number of studies have now shown higher paraben concentrations with increasing use of PCPs used in the past 24 hours. In particular, the use of colognes and perfumes has been associated with increased methylparaben concentrations in both adults and 8–13 year old children. Other PCPs associated with increased methylparaben concentrations include lotions, colored cosmetics (hair dye, foundation, blush, eye shadow, eye liner, or mascara), aftershaves and nail polish in adults and hair care products and deodorants (girls only) in children.

Many studies have now linked parabens to reproductive, endocrine, respiratory and other health problems including cancer, birth defects, infertility, contact allergies, and a host of other problems. Many studies have suggested possible chronic health effects of parabens, including increased risk of breast cancer and prostate cancer through estrogenic activity, and possibly increased risk of skin cancer.   Parabens have also been linked increases in estrogenic activity in children, leading to decreased fertility in males early puberty in females including early breast development.

Natural estrogens act in target cells by binding to estrogen receptors which function to regulate gene expression. However, parabens have the ability to remain longer within the body and accumulate than their short‑lived natural counterparts. Studies have also found the estrogenic effects of parabens at doses at the same levels reported in many studies.

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Breast cancer

A number of studies have suggested that products containing parabens that are regularly used around the breast area, are contributing to the increase in breast cancers. In particular, products such as deodorants and anti-perspirants applied to, and left on the underarm area for long periods, thus able to absorb through the skin and accumulate in the underlying tissue. Studies show that around 54% of incidences of breast cancer were located around the underarm area.

In addition, an analysis of breast tissue samples collected during mastectomy performed for primary breast cancer showed that at least one paraben was detectable in virtually all samples (99%) because estrogen is known to play a central role in the development, growth, and progression of breast cancer. The mechanisms by which parabens contribute to breast cancer is now well established and shows they enable multiple cancer steps. Of great concern is also that combinations of different parabens can produce additive effects on proliferation and most paraben containing products have multiple parabens in them. They can act synergistically to increase breast cancer gene expression and the presence of multiple estrogen receptors and other areas where they can bind in breast tissues may even increase the activity of parabens.

The influence of paraben on estrogen activity may be exacerbated by the fact that many personal care products containing parabens are applied directly around the breast area, as is the case with underarm deodorants and body moisturisers. Clinical studies over the last decade have indicated the majority of breast cancers occur in the upper‑outer quadrant of the breast near to the underarm area where products are applied. Not only are these products then able to be directly absorbed but regular re-application can promote the bioaccumulation of paraben in breast tissue. Underarm cosmetics can penetrate the skin more efficiently as they are applied to an area which usually has nicks and abrasions, caused by shaving and other forms of hair removal. The frequent application of these PCPs and the fact that they are left upon the skin of the breast region means that the dermal area is constantly and regularly exposed leading to accumulation in the underlying tissues.

Studies as early as 1983 have suggested links with negative reproductive effects. This study found that six preterm infants had significant concentrations of methyl paraben and its metabolites present in their urine. While more recent studies have found that exposing pregnant female mice to small levels of environmental estrogens could lead to a termination during early pregnancy.  

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Male bits and Mens issues

In recent decades reproductive and developmental problems have become more prevalent—for example, data from the Centers for Disease Control and Prevention (CDC) show that male reproductive problems, including undescended testicles and hypospadias, doubled between 1970 and 1993. A rising concern has emerged regarding possible adverse effects of chemicals in cosmetics and PCPs on human reproduction outcomes. In developed countries about 15% of human couples are affected by infertility, almost half of these cases attributed to men, through low sperm motility or/and sperm count. Since they tend to mimic female hormones, these compounds especially affect male reproductive function.

Products containing parabens have been linked to negative effects on the male reproductive system and that exposure to paraben, particularly butyl paraben, while in the womb and in young males can lead to decreased testosterone levels and reduced sperm counts. Parabens appear toxic to the mitochondria and adversely affect mitochondrial function in the testes. The daily sperm production and the efficiency in the testes decreased dramatically in the test groups who received parabens. The sperm counts in the studies decreased in a dose dependent manner, that is the higher the paraben levels the lower the sperm counts. Other studies have also shown exposure to pregnant female rats led to male offspring with decreased testes, seminal vesicle and prostate gland weights, as well as decreased sperm count and motility.

Parabens have also been associated with allergic reactions (sensitisation); commonly rashes, swelling and itchiness and contact dermatitis (skin inflammation). An extensive range of adverse effects on the skin have been reported, including changes to cell structure, changes to gene expression, protein synthesis and cell death, following one month daily application of paraben based formulations. Studies are also showing chronic skin application of parabens may lead to prolonged estrogenic effects in skin. Estrogens are very important hormonal regulators in the skin and function to preserve collagen content, which supports and maintains elasticity thickening of the skin and wound healing. Daily application of products containing methylparaben to the skin found that the methylparaben remained unmetabolised on the skin and affected the ability of the skin act as a protective barrier so dermatological disorders, skin irritation and skin allergies often follow. Short term application to the skin of animals resulted in edema, which is swelling due to a collection of fluids, desquamation, which is a shedding of the skin, and erythema, which is a reddening of the skin due to dilation of the blood vessels. Similar affects have also been observed in human studies.

Overall this is a group of chemicals that we really do need to avoid but even reading the labels does not guarantee there will be no parabens.

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