Dr Dingle's Blog / depression
Depression itself is not a disease, but a symptom of an underlying problem. A new theory called the “Immune Cytokine Model of Depression” holds that depression is a “multifaceted sign of chronic immune system activation,” inflammation. Depression may be a symptom of chronic inflammation. And a large body of research now suggests that depression is associated with a low-grade, chronic inflammatory response and is accompanied by increased oxidative stress—not a serotonin imbalance.
Researchers discovered in the early 1980s that inflammatory cytokines produce a wide variety of psychiatric and neurological symptoms that perfectly mirror the defining characteristics of depression. Cytokines have been shown to access the brain and interact with virtually every mechanism known to be involved in depression including neurotransmitter metabolism, neuroendocrine function, and neural plasticity.
This is now supported by increasing lines of scientific evidence including:
- Depression is often present in acute, inflammatory illnesses.
- Higher levels of inflammation increase the risk of developing depression.
- Administering endotoxins that provoke inflammation in healthy people triggers classic depressive symptoms.
- One-quarter of patients who take interferon, a medication used to treat hepatitis C that causes significant inflammation, develop major depression.
- Up to 50% of patients who received the cytokine IFN-alpha therapy to help treat cancer or infectious diseases developed “clinically significant depression.”
- An experiment involving the administration of a Salmonella typhi vaccine to healthy individuals produced symptoms of fatigue, mental confusion, psychomotor slowing and a depressed mood. These symptoms correlated with the increase in cytokine concentrations.
- Remission of clinical depression is often associated with a normalization of inflammatory markers.
- There is now a large body of literature regarding laboratory animals demonstrating that cytokines … can lead to a host of behavioural changes overlapping with those found in depression. These behavioral changes include decreased activity, cognitive dysfunction and altered sleep.
- All the activities associated with reducing the prevalence of depression and depression symptoms are anti-inflammatory. These include increased sunlight and time spent outside, exercise and physical activity, relaxation and meditation techniques, healthy eating as well as administering anti-inflammatory nutritionals.
There is further support from large epidemiological studies. A number of longitudinal studies have now shown that inflammation in early adulthood predicts depression at a later stage in life. In a large longitudinal study, the risk for depression and psychotic experiences in adolescence was almost two-fold higher in individuals with the highest compared to the lowest levels of inflammation as indicated by interleukin-6 (IL-6) levels in childhood. Children who were in the top third of IL-6 levels at the age of 9 years were 55% more likely to be diagnosed with depression at the age of 18 than those with the lowest childhood levels of IL-6. Children in the highest level of IL-6 levels at the age of 9 were also 81% more likely to report psychotic experiences at the age of 18. A study of more than 73,000 men and women showed increasing inflammation levels were associated with increasing risk for psychological distress and depression. Increasing inflammation (CRP) levels were also associated with increasing risk for hospitalization with depression.
In support of the inflammation depression link, recent studies have found a significant link between the dietary inflammatory index (DII) and risk of depression. In an Australian study of 6,438 middle-aged women, those with the most anti-inflammatory diet had an approximately 26% lower risk of developing depression compared with women with the most pro-inflammatory diet. Similarly, a study in the UK examined the DII and recurrent depressive symptoms over five years in 3,178 middle-aged men and 1,068 women. Researchers found that for each increment of 1 level of DII score (increased inflammation), odds of depression increased by 66% in women, whereas in men the risk increased by only 12%. In a study of 15,093 university graduates in Spain, those on the highest DII (strongly pro-inflammatory diet) had a 47% risk of depression compared with those in the bottom, with a significant dose-response relationship, which means as the diet became more inflammatory it increased the risk of depression. Further analysis also showed the association between DII (the inflammatory diet) and depression was stronger among participants older than 55 years, with an increased risk of 270% and those with cardiometabolic comorbidities (high blood pressure, diabetes, etc.) had an 80% increased risk of depression. In a study of 43,685 women (aged 50–77) without depression at baseline, the risk of developing depression was 41% higher if they were on the highest compared to the lowest Dietary Inflammatory Index diet.
Oxidative stress is closely related to the inflammatory pathway in particular. Pro-inflammatory cytokines are produced in reaction to oxidative stress and oxidative stress in turn amplifies the inflammatory response. High cortisol levels have been associated with increased levels of oxidative damage. Depression has been associated with increased oxidative stress and increased severity of depression is associated with increased systemic oxidatively generated DNA and RNA damage. Severe depression is associated with increased systemic oxidatively generated RNA damage, which may be an additional factor underlying the somatic morbidity and neurodegenerative features associated with depression. In a meta-analysis, 1,308 subjects depressed persons had increased oxidative stress and decreased anti-oxidant defences (as measured by 8-OHdG and F2-isoprostanes). The results indicate that depression is associated with increased oxidative damage to DNA and lipids. The brain is particularly vulnerable to oxidative damage due to its high oxygen consumption and low antioxidant defences. Sustained oxidative brain damage during a depressive episode may make a sufferer prone to developing another depressive episode. Therefore, it has been hypothesized that exposure to oxidative stress could be an explanatory mechanism in the remitting and chronic course of depressive disorders. There is also evidence from post-mortem studies suggesting that in depression oxidative stress is increased and antioxidants are decreased in the brain.
A study of 37 patients with bipolar disorder showed that bipolar disorder is associated with increased oxidatively generated damage to nucleosides, which could be contributing to the increased risk of medical disorders, shortened life expectancy, and the progressive course of illness observed in bipolar disorder. Another study showed increased oxidative stress as indicated by increased nitric oxide (NO) and lipid peroxidation, measured by thiobarbituric acidic reactive substance (TBARS) assay in patients with bipolar disorder.
There is evidence suggesting that antioxidants are decreased in depression, illustrated by lower antioxidant levels, including carotenoids, and antioxidant enzymes. There is some evidence to suggest that antidepressants have antioxidant properties and may act through reducing pro-inflammatory cytokines and ROS production and improving levels of antioxidants such as superoxide dismutase.
 Miller et al. 2009.
 Berk et al. 2011.
 Miller 2009.
 Brydon et al. 2008.
 Dantzer et al. 2008.
 JAMA Psychiatry 13, 2014.
 Wium-Anderson et al. 2013.
 Nitin Shivappa et al. 2016 British Journal of Nutrition.
 Akbaraly et al. Clinical Psychological Science 2016.
 Sanchez-Villegas A et al. British Journal of Nutrition 2015.
 Lucas et al. 2014.
 Joergensen et al. 2011.
 Jorgensen et al. 2013; Pandya et al. 2013.
 Black et al. 2014; Palta et al. 2014.
 Moylan et al. 2013.
 Wange et al. 2009; Michel et al. 2012.
 Gawryluk et al. 2011.
 Munkholm et al. 2015.
 Andreazza et al. 2008.
 Palta et al. 2014.
 Milaneschi et al. 2012.
 Sarandol et al. 2007.
 Khanzode et al. 2003; Lee et al. 2013.
Nutritional deficiencies are now a recognized risk factor for psychiatric disorders, while excessive intake of nutrient poor foods is predictive of poor mental health, while a healthy diet reduces risk.
For example studies have shown low blood levels of certain nutrients in psychiatric disorders, folate (B9) and B12 are often deficient in schizophrenia, and are associated with symptom severity. That is the lower the levels the higher the symptoms. While on the other side supplementing with B-vitamins can significantly reduce symptoms of schizophrenia and reverse some of the conditions associated with the disorder.
Antioxidant vitamins like C and E are also lower in long-term schizophrenia patients, potentially contributing to the elevated oxidative stress and inflammation observed in this population. While vitamin D is involved in the onset of schizophrenia and is associated with worsened physical and mental health outcomes the lower it goes. Zinc and selenium, are also low in people with schizophrenia and depression.
By making small positive changes in our eating we can achieve vast improvements in our mental health.By eating healthy, nourishing foods we are supplying our brain with the nutrients it needs to make neurotransmitters, ensuring brain cells function at their optimal levels. When neurotransmitters are out of balance, it is easy for us to feel anxious, stressed, depressed and uninterested. For example, if dopamine, the ‘feel good’ neurotransmitter, levels in the brain fall below the desired level, an individual’s capacity to feel happy, excited, or motivated, becomes limited also.
We can take measures to prevent against such mood states by ensuring we consume foods with adequate nutrients to ensure the desired level of neurotransmitters are maintained.
Just as important a large body of evidence shows the role of feeding the gut microbiome can have a dig impact on our mental health and mental health states. But more on that later
Research on 59 participants, those who were confirmed night owls (preferring late to bed and late to rise) had lower integrity of the white matter in various areas of the brain (Rosenberg et al 2014). Lower integrity in these areas has been linked to depression and cognitive instability.
Sleep and weight
Obesity in another disorder linked with insomnia. Research shows that diets that are higher in saturated fats are more susceptible to chronic diseases and disorders which includes insomnia (Novak et al. 1995). This is an alarming fact as 20% of the population of the United States of American are overweight or obese (Patterson et al. 2004).
Many studies, including one spanning twenty years, have tested the hypothesis that sleep and obesity are linked and the majority of results show positive correlations (Gangwisch et al. 2005). Further studies, with over 500,000 total participants via meta‑analysis have supported obesity and insomnia in adults and children (Cappuccio et al. 2008). The trends of increasing BMI and reduced sleep hours appear to go hand in hand, along with sleeping troubles related to Sleep Apnoea often seen in obese patients.
This link between Obesity and the symptoms of its associated diseases demonstrates a common trend towards diminishing an individual’s peak performance. Obesity and many of the health conditions which result from it increase the lower productivity levels associated with lower mental and cognitive functioning.
Obesity is also a serious factor in poor sleep habits. In a number of studies obesity was associated with "reduced sleeping hours " (Ko et al (2007). Obesity, particularly abdominal and upper body obesity, is the most significant risk factor for Obstructive Sleep Apnea (OSA). Patients with sleep apnea often experience daytime sleepiness and difficulty concentrating (Teran-Santos et al, 1999). Studies have also shown a strong association between sleep apnea and the risk of traffic accidents (Terán-Santos et al (1999). In fact, subjects suffering from sleep apnea were at a higher risk than those who had consumed alcohol to be involved in a traffic accident. This has major implications, particularly for overweight and obese workers using any form of equipment of driving vehicles.
This lack in sleep will then leave the employee going to the work already feeling tired, irritable and stressed, therefore making it difficult to concentrate, and highly increasing the chances of being injured or making a mistake which may put fellow workmates in danger (Lynch, 2005) It is situations like this, where the worker comes to work already feeling tired, that the employee is putting his safety and other's safety at risk.
Shift workers are known to be a high-risk group for obesity. In the current study population, rotating-shift workers showed a higher distribution of the highest body mass index compared with daytime workers
In a study of the brains of 24 participants after both a good and a bad night’s sleep. after disturbed sleep, there was increased activity in the depths of the brain, areas which are generally associated with rewards and automatic behaviour. It seems a lack of sleep robs people of their self-control and so their good intentions are quickly forgotten.
What we have discovered is that high-level brain regions required for complex judgments and decisions become blunted by a lack of sleep, while more primal brain structures that control motivation and desire are amplified.”
In other words: lack of sleep robs people of their self-control and so their good intentions are quickly forgotten.
On top of this, the researchers found that after being deprived of sleep, participants displayed greater craving for high-calorie junk food. The more sleep-deprived they were, the greater the cravings. A stufy of 13,284 teenagers found that those who slept poorly also made poor decisions about food. Similarly, a Swedish study found that at a buffet, tired people were more likely to load up their plates.
The link has even been made from poor sleep through to food shopping. A Swedish study found that men who were sleep-deprived bought, on average, 9% more calories than those who’d had a good night’s sleep. These results were likely the result of the poor decision-making. It had been thought that the tendency to eat more after poor sleep was related to the so-called ‘hunger hormone’ ghrelin. But the latest studies suggest that it’s simple self-control that is most important in causing the sleep-deprived to over-indulge.
When health is absent, Wisdom cannot reveal itself, Art cannot manifest, Strength cannot be exerted, Wealth becomes useless, And reason is powerless." — Herophilus 300 B.C.
Our work places are either a great place to promote health or to contribute to the health problem. Our work environments are experiencing an emerging health crisis from longer workdays, deskbound occupations, access to poor quality foods and poor physical activity. In many cases they are contributing to a deterioration in employee health as our work and the workplace has the potential to have a significant affect on the mental, physical, economic and social well-being of workers. Major concerns in the work environment are work-related stress, obesity, diabetes, cardio vascular disease, fatigue , poor sleep and the many other conditions that come from these. Many of our workplaces for example have increased the risk of putting on weight due to sedentary practices, stress and long and awkward work hours. This of course has the potential to lead to many other chronic health conditions which cost the individual, community and employers. From an employers perspective poor health has the potential to reduce the quality of work and productivity within many workplaces and is likely costing the economy billions of dollars in workplace productivity alone. While the costs of workplace productivity are significant it is also likely that some obesogenic (increasing the risk of putting on weight) environments are likely to be the focus of legal action as the rates of illness and obesity increase. This is particularly the case for inflexible workplace, long hours and shiftwork.
An employee’s health and productivity at work is not only affected by their work environment but also by factors that are not work related. These factors vary between individuals and depend on the individuals chosen lifestyle outside of work. However, through empowering staff members on healthy lifestyles the overall health management of individuals will benefit not only the company but also the broader community. Wellness in the workplace is influenced by many different factors including the communication between co-workers and employers, physical demands especially in sedentary occupations and the eating habits, lifestyles of employees and much more.
When it comes to common health issues of most employees, wellness programs can provide an easy and cost effective solution. Fatigue, stress, depression and obesity are commonly interrelated and increasingly common in most workplaces. The workplace has been viewed as an attractive place for wellness programs as it has established communication channels and it provides a convenient, familiar physical and social setting. In addition, it serves to benefit the employers from the improved health of employees.
Many factors contribute towards the creation of a healthy employee who is able to work consistently at a high level of efficiency and productivity; however health is one of the most important determinants. The costs of unhealthy workers are usually measured by employers in terms of easily quantifiable direct health costs such as medical claims, disability funds and compensation payouts. In the US where figures are more easily accessed because the employer has been traditionally responsible for health care cost, compared with employees who are struggling, thriving employees have 41% lower health-related costs to the employer, a difference of $2,993 per person. For every 10,000 employees, this represents a difference of nearly $30 million to the employer. However, when looking at the health/productivity costs borne by employers, only a small portion of these expenditures are direct medical costs. Indirect costs are more difficult to distinguish and measure, they include those costs incurred from employee mortality, absenteeism and the reduced productivity and presenteeism including poor concentration and focus, low output, and disruption of other workers evident in an employee while still working.
An employee health behaviors are strong predictors of job performance and absenteeism. Many studies have demonstrated the link between poor health factors and absence from work including positive associations between absenteeism and obesity, stress, physical inactivity, and hypertension. While the frequency and severity of poor health are directly related to days absent from work. Healthier workers work more and are away less.
The loss of a qualified professional due to moving to a new job, illness or even death can often be difficult and costly for the organization to replace. The cost of rehiring and retraining a suitable replacement could result in large organizational outlays of time and money, well in excess of $100,000. Not only will a new candidate be difficult and costly to find, but an immense amount of expertise, experience and organizational knowledge will be lost. Karoshi is a term coined in Japan, literally translating into ‘death from overwork’ in English. Karoshi is described as ‘unexplained death’ thought to arise due to a combination of elevated working hours, high stress and poor health, with the major medical causes of death being heat attack and stroke. In Japan working weeks that exceed 60 hours are not an exception. The first case of karoshi was reported in 1969 where a 29 year old married man died from a stroke and his death could not be attributable to anything other than occupational stress and chronic overwork. In 1994 the Japanese Government’s Economic Planning Agency in the Institute of Economics estimated the number of karoshi deaths at around 1,000 or 5% of all deaths as a result of cerebrovascular and cardiovascular disease each year within the 25-59 age group.
In the US the cost of turnover per person employed who is healthier is 35% lower than that of those who are struggling. For every 10,000 employees, this represents $19.5 million. Although turnover is more common among younger employees, higher wellbeing was predictive of lower turnover and lower turnover costs in the next year for younger and older employees alike. Those who were struggling or suffering in overall wellbeing were more than twice as likely as those who were thriving to say they would look for another job if the job market improves. This means that the actions that employers take today to improve health — in addition to improving job performance — are likely to have important implications on the moves employees make in the future.
Presenteeism represents a cost that is difficult to quantity but a large contributor to lost productivity. Many people are under the flawed assumption that when people are at work that they are productive, however if employees are sick, injured, stressed or burned-out in the workplace, they are not working to full capacity. Presenteeism is the worker coming in who shouldn’t and in the process is not just less productive but may also be reducing the productivity of other employees. This doesn’t just occur over health but when a person is sick they may be slowing everyone else down. Presenteeisms result in a negative impact not only on the quantity of work completed, but also on the quality of products, services, decisions, and co-worker and customer interactions. Although presenteeism cannot be directly quantified in a straightforward manner many studies now suggest it may be one of the biggest costs to employees. So you might be better off staying away from work when you are sick.
Unhealthy workers are also more likely to have workplace accidents and healthy and focused employees is less likely to endanger themselves and other co-workers through negligent behavior caused by poor physical and psychological health. A number of studies have now found that investing in wellness programs and the health of employees can reduce accidents. This also includes accidents on the way home from work if an employee is fatigued or distracted with their health. Accidents are expensive for all companies because of downtime, the resources that need to be dedicated to investigation, lost productivity from injured workers and workers’ compensation. In Australia, workers’ compensation costs are unacceptably high, reflecting relatively high frequency rates of occupational injuries which may be prevented through a wellness program.
The direct cost of stress is more than $20 billion to the Australian economy, and around two thirds of that to Australian employers because of stress-related presenteeism and absenteeism. 95% of all claims for mental disorders in the past ten years are for mental stress. These claims are the most expensive type of workers’ compensation claim due to their typically lengthy periods of work absence. Professionals make more mental stress claims than any other occupation, mostly for work pressure. This is despite the fact that the Australian Bureau of Statistics (ABS) Work-related Injuries Survey 2009–10 which showed that 70% of workers who reported they experienced work-related mental stress did not apply for workers’ compensation.
Productivity is affected heavily by seasonal illnesses and their available treatments. Allergies are a highly prevalent condition in the general population affecting people in varying ways. Symptoms of allergies include itching and irritation of the nose; watery nasal discharge, nasal congestion, sneezing and are often accompanied by fatigue, weakness, malaise, irritability and decreased appetite. Studies now show that individuals with allergy disorders generally score lower on tests on social functioning, role limitation, mental health and energy / fatigue and pain compared to controls. In the US allergy disorders result more than 4 million workdays lost per/year in the United States.
However, it is not just the disorder the can have an effect on productivity; the drugs used to treat the illness may also affect productivity levels. Medications are also often a hidden cost in presenteeism, accidents and lost work productivity. The use of sedating antihistamines for allergies had a 50% higher risk of on-the-job injury than control subjects. Another study found that driving impairments exhibited due to the use of a sedating antihistamine were worse than that connected with a blood-alcohol concentration of 0.1%. In a study of nearly 6000 employees those who used sedating antihistamines experienced on average an 8% reduction in daily work out-put compared to those who used non-sedating antihistamines. Many other medications including pain killers and cholesterol lowering drugs can result in lost productivity. The fatigue and muscle soreness created by cholesterol lowering drugs may impact productivity especially those with more physical work. While their effect on memory may be even more problematic. A colleague of mine recalled the effect these drugs were having on the memory of police officers who were called to be witnesses. Awkward eh.
The message is that it is in everyone’s best interests to promote health, both the individual and the company they work for. The good thing in all of this is that companies are increasingly adopting workplace wellness programs which if adopted well can make a big difference to the health of their employees.
“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)
- Watson et al
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- Murtagh et al., 2015
- Son and Lee. 2001
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- Alonso-Frech et al 2011;
- Norton S et al 2014
- Ahlskog 2011;
- Pitkälä et al. 2013
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- Gondola, 1986, 1987
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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
- Time of day (energy levels)
- low self esteem
- peer/social pressure
- media and advertising
- low price/convenient
- mental stimulation
- too busy
- Feeling Unloved
- Anxious or restless
- Angry or jealous
- Dissapointed or rejected
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.
Not only are probiotics considered beneficial to digestive health, and immune health but increasing evidence suggests direct and indirect interactions between gut microbiota (GM) and the central nervous system (CNS).
A large body of research has supported the presence of a pathway of communication between the gut and the brain, modulated by the gut microbiota, giving rise to the term “microbiota-gut-brain” axis. It is now thought that, through this pathway, microbiota can affect behaviour and modulate brain plasticity and cognitive function. In particular, studies have illustrated an association between the gut microbiota composition and cognitive processes such as learning and memory. Research has shown that the intestinal microbiota additionally contribute to the early development of normal social and cognitive behaviours 1. While probiotic and prebiotic supplementation can have a positive effect on mood and psychological symptoms such as depression and anxiety, stress as well as mental health issues including depression, Alzheimers and Parkinson’s diseases. This new area of research, called “psychobiotics” is where the beneficial bacteria (probiotics) or prebiotics that influence bacteria–brain relationships can exert positive emotional, cognitive, systemic, and neural benefits 2. This process is thought to occur primarily through the central nervous system (CNS) as well as through metabolic, hormonal and immune pathways.
Recent evidence indicates a clear association between changes in the microbiota and cognitive behaviors and there is increasing evidence on the effects of supplementing with probiotics on improving cognitive disorders 3. One of the earliest studies found that the wrong type of bacteria added to the gut of germ free animals (containing no microbiota), can cause stress related negative behavious while administration of probiotics can improve cognitive behaviors including learning and memory 1.
In a clinical trial conducted among 60 Alzheimer's patients where the probiotic supplemented group took 200 ml/day probiotic milk for 12 weeks, the probiotic group showed a significant improvement in the MMSE (Mini-mental state examination) which is a measure of cognitive function. In addition, they reported lower levels of oxidation and inflammation, blood fats (tryglicerides) and improved insulin resistance and Beta cell (pancreas) function which controls and stores insulin in the probiotic group compared to the control group 4. A pretty good reason to supplement with probiotics.
Growing research also shows probiotic supplements may be used therapeutically to modify stress responses and symptoms of anxiety and depression 5,6,7,8. One study found that a short 3-week intervention with probiotics-containing milk drink improved mood scores compared to participants who received a placebo. Although, improvement in mood was only observed for participants who showed elevated symptoms of depression at the beginning 9. A second study found that a month of probiotic supplementation significantly improved depression and anger 10. In a triple-blind study of 20 healthy participants without a current mood disorder over 4 weeks, probiotics significantly reduced negative thoughts associated with a sad mood compared to placebo. The positive effect was mostly because of reduced rumination and aggressive thoughts 11. While a study of people with chronic fatigue syndrome found that supplementing with probiotics for 2 months significantly reduced their anxiety scores 12.
Similar results have also been shown in animal studies. In a study of healthy mice researchers observed a reduction in anxious and depressive behavior after feeding healthy mice with probiotics 13. A similar result was shown in adult rats with a reduction in depressive-like behaviors after feeding them with Bifidobacterium species. The effect was comparable to the effects of administering the antidepressant citalopram 14.
Stress and anxiety disorders are two of the most common psychiatric illnesses worldwide, affecting both children and adults. Increasing numbers of studies have suggested that the gut microbiota is involved in the pathophysiology of stress-related disorders. For example, a number of studies have now shown that certain strains of bacteria increase anxious behaviour while others reduce it. One study found that participants who were given a mixture of probiotics containing Lactobacillus and Bifidobacterium species showed significantly less psychological distress than matched controls 15. A recent (November 2016) meta-analysis of seven studies with around 300 participants showed that supplementation with probiotics resulted in a significant improvement in psychological symptoms of depression, anxiety, and perceived stress in healthy human volunteers 16.
However, probiotics and the effects on our moods appears to be a two way street. While the gut microbiome can alter moods, our moods can also alter our gut microbiome. Chronic stress can cause behavioral, cognitive, biochemical, and gut microbiota aberrations. In a study of 1002 cases and controls followed up for 12 years, those with gut disorders had elevated levels of anxiety and depression at baseline, but also those with higher levels of anxiety and depression were more likely to have gut disorders at follow-up 17.
Animal studies have also shown certain strains of Lactobacillus exert a positive effect on anxiety-related behavior and responses to stress 13,18. In a study on rats subjected to 21 days of stress the results showed that administration of probiotics improved the stress-induced behavioral (anxiety and depression) and cognitive dysfunction, showing an effect similar to and better than that of an antidepressant. It also resulted in lower stress hormones and improved blood parameters suggesting it was dealing with some of the underlying mechanisms 18.
Other studies have noted that microbiota have an important influence on the development of cognitive processes in young mice 1. Depletion of a normal gut microbiome in early life, especially during the post-weaning period, may affect cognitive and social behaviours in the brain through the alteration of neuropeptides (chemical messengers) such as vasopressin and oxytocin 19,20. In fact, the research suggests a strong role of the gut microbiota in autism spectrum disorder. Interestingly, treatment of mice with autism with probiotics has shown to ameliorate autism related traits 21. In another twist on this, a study of 75 pregnant women given probiotics 4 weeks before their due dates and then continued giving the probiotics to the infants, or to the mothers if they were breastfeeding for 6 months did not develop any ADHD or Asperger’s after being followed for 13 years. 17.1% of the children in the placebo group developed ADHD or Asperger’s. Not one child in the probiotic group did 22.
Importantly, studies have shown that multispecies probiotics (i.e., combining different strains of specific genera) can have increased effectiveness through an additive effect of specific strain properties such as colonization of different niches, enhanced adhesion and induction of an optimal pH range, as compared to mono-species supplements 23,24. So take a mixed species supplement for the best results.
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