New research from the University of South Australia and University of Exeter in the UK has found the strongest evidence yet that obesity causes depression, even in the absence of other health problems. The research, published in the International Journal of Epidemiology, shows that the psychological impact of being overweight causes depression, rather than associated illnesses such as diabetes.
Researchers looked at UK Biobank data from more than 48,000 people with depression, comparing them with a control group of more than 290,000 people born between 1938 and 1971, who provided medical and genetic information. Hospital data and self-reporting were used to determine whether people had depression.
“We separated the psychological component of obesity from the impact of obesity-related health problems using genes associated with higher body mass index (BMI), but with lower risk of diseases like diabetes,” says UniSA Professor Elina Hypponen, director of the Australian Centre for Precision Health and co-leader of the study. “These genes were just as strongly associated with depression as those genes associated with higher BMI and diabetes. This suggests that being overweight causes depression both with and without related health issues - particularly in women.”
At the other end of the BMI spectrum, very thin men are more prone to depression than either men of normal weight or very thin women. “The current global obesity epidemic is very concerning,” Hypponen added. “Alongside depression, the two are estimated to cost the global community trillions of dollars each year. Our research shows that being overweight doesn’t just increase the risks of chronic diseases such as cancer and cardiovascular disease; it can also lead to depression.”
Can Vitamin D Supplements Promote Weight Loss In Obese Children?
Vitamin D supplements may promote weight loss and reduce risk factors for future heart and metabolic disease in overweight and obese children, according to research presented at the recent European Society for Paediatric Endocrinology annual meeting. These findings indicate that simple vitamin D supplementation may be part of an effective strategy to tackle childhood obesity and reduce the risk of serious health problems, such as heart disease, in adulthood.
Obesity in childhood and adolescence represents a major health problem worldwide, which leads to the development of expensive, serious and debilitating complications, including heart disease and diabetes, in later life. Although vitamin D deficiency is typically associated with impaired bone health, in recent years it has been increasingly linked with increased body fat accumulation and obesity, with the precise nature of this relationship currently under intense investigation by researchers. However, the effect of vitamin D supplementation on the weight and health of obese children and adolescents had not yet been investigated.
Dr. Christos Giannios, Professor Evangelia Charmandari and colleagues at the University of Athens Medical School and the 'Aghia Sophia' Children's Hospital in Athens, assessed 232 obese children and adolescents over 12 months, with 117 randomly assigned to receive vitamin D supplementation, in accordance with the Endocrine Society's guidelines on treatment and prevention of deficiency. Levels of vitamin D, body fat, and blood markers of liver function and heart health were assessed at the start of the study and 12 months later.
The study reported that children given vitamin D supplements had significantly lower body mass index, body fat and improved cholesterol levels after 12 months of supplementation. "These findings suggest that simple vitamin D supplementation may reduce the risk of overweight and obese children developing serious heart and metabolic complications in later life," Charmandari said.
The team now plans to investigate the effects of vitamin D supplementation on the health of obese children and adolescents that already have unhealthy conditions, such as high blood pressure, high blood glucose and high cholesterol, all of which increase the risk of heart disease, stroke and diabetes. "Although these initial findings indicate that vitamin D could be used in the treatment of obesity, there remains a lack of evidence on the safety and long-term effects of supplementation, particularly if there is no vitamin D deficiency. Charmandari added. “However, if your child is overweight or obese I recommend that you consult your primary care physician for advice, and consider having their vitamin D levels tested."
Improving Health Markers In Obese Women
According to new research, obese women with polycystic ovary syndrome (PCOS) may be able to improve their health outlook with a particularly enjoyable form of therapy: regular sessions in a hot tub. The research found that soaking in a hot tub several times per week for two months resulted in improved measures of cardiovascular health, beneficial changes in fat tissue and other improvements suggestive of a reduced risk of diabetes or other metabolic disorders.
PCOS - which affects one in 10 women of childbearing age - is a complex endocrine disorder often marked by abnormal menstrual cycles, high testosterone levels and cyst formation on the ovaries. It is associated with infertility along with increased risk of obesity and diabetes, outcomes that are thought to be related to inflammation and dysfunction in fat tissue. "Our findings are exciting because repeated heat exposure appears to reverse some of the inflammation in fat that may be causing metabolic health impairment in this population," says Brett Romano Ely, a doctoral candidate in the University of Oregon department of human physiology who conducted the study. "Along with this reduction in inflammation, we observed improvements in functional outcomes related to insulin resistance. This means that regular hot tub use could potentially be used as a therapy in populations with an elevated risk of developing metabolic diseases like type 2 diabetes."
Heat Therapy Benefits
The research adds to a growing body of evidence for the health benefits of heat therapy. It is the first study to examine impacts in women with PCOS and the first to look at changes in fat tissue before and after heat therapy.
In the study, six obese women with PCOS underwent one-hour sessions in a hot tub three to four times per week for about two months. Researchers analyzed samples of fat tissue taken at the beginning and end of the study and also tested insulin sensitivity in four of the women. At the end of two months, the women showed reductions in fasting glucose during an oral glucose tolerance test - indicating a reduced risk of developing diabetes - reduced blood pressure and heart rate - indicating a reduced risk of heart disease - and other improvements in measures of heart health and metabolism. Surprisingly, some participants reported having regular menstrual cycles during the study, suggesting that heat could help mitigate some of the underlying physiological processes involved in PCOS.
Researchers speculate that sitting in a hot tub can yield some of the same benefits as aerobic exercise because both activities raise body temperature. This triggers an increase in the flow of blood to the skin as a cooling mechanism. "We see blood flow patterns in subjects in the hot tub that look like what we see in subjects during aerobic exercise, so this change in blood flow may have a similar benefit to exercise on blood vessel health," Ely said.
In addition, heat exposure causes the body to increase proteins known as heat shock proteins, which are involved in reducing inflammation, repairing damaged insulin receptors and improving blood vessel structure and function. The researchers found levels of some heat shock proteins were increased in fat tissue after the heat therapy, indicating that these proteins could play a role in the reduced inflammation and improved insulin sensitivity they observed in the women. While the researchers saw some improvements after the first month of regular hot tub use, most improvements took the full two months to become apparent.
Study Finds That More Than Two Billion People Overweight Or Obese
Globally, more than two billion children and adults suffer from health problems related to being overweight or obese, and an increasing percentage of people die from these health conditions, according to a recent study. They are dying even though they are not technically considered obese, researchers found. Of the 4.0 million deaths attributed to excess body weight in 2015, nearly 40 percent occurred among people whose BMI fell below the threshold considered "obese."
The findings represent "a growing and disturbing global public health crisis," according to the authors of a paper published recently in The New England Journal of Medicine. "People who shrug off weight gain do so at their own risk - risk of cardiovascular disease, diabetes, cancer, and other life-threatening conditions," says Dr. Christopher Murray, an author on the study and Director of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington. "Those half-serious New Year's resolutions to lose weight should become year-round commitments to lose weight and prevent future weight gain."
The study spans 195 countries and territories from 1980 through 2015. It is based on data from the most recent Global Burden of Disease study (GBD), a systematic, scientific effort to quantify the magnitude of health loss from all major diseases, injuries, and risk factors by age, sex, and population. With more than 2,300 collaborators in 133 countries, the GBD study examines 300-plus diseases and injuries.
The paper includes analyses of other studies on the effects of excess weight and potential links between high BMI and cancers of the esophagus, colon and rectum, liver, gallbladder and biliary tract, pancreas, breast, uterus, ovary, kidney, and thyroid, as well as leukemia.
Understanding High Body Weight
IHME is committed to producing more in-depth studies on the implications of obesity and being overweight, including through a new partnership with the United Nations, according to Dr. Murray. He announced at the forum a new agreement between IHME and the UN's Food and Agriculture Organization (FAO) to exchange data, knowledge, and expertise. The goal is to elevate the world's collective understanding of what is driving "the current global epidemic of disease" related to high body weight. The United Nations "Decade of Action on Nutrition" is an initiative covering 2016-2025 to eradicate hunger, end malnutrition in all its forms - undernutrition, micronutrient deficiencies, overweight or obesity - and reduce the burden of diet-related non-communicable diseases in all age groups.
In 2015, excess weight affected 2.2 billion children and adults worldwide, or 30 percent of all people. This includes nearly 108 million children and more than 600 million adults with BMI exceeding 30, the threshold for obesity, according to the study. The prevalence of obesity has doubled since 1980 in more than 70 countries and has continuously increased in most other nations. Although the prevalence of obesity among children has been lower than among adults, the rate of increase in childhood obesity in many countries was greater than that of adults.
Among the 20 most populous countries, the highest level of obesity among children and young adults was in the United States at nearly 13 percent; Egypt topped the list for adult obesity at about 35 percent. Lowest rates were in Bangladesh and Vietnam, respectively, at 1 percent. China with 15.3 million and India with 14.4 million had the highest numbers of obese children; the United States with 79.4 million and China with 57.3 million had the highest numbers of obese adults in 2015. "Excess body weight is one of the most challenging public health problems of our time, affecting nearly one in every three people," said Dr. Ashkan Afshin, the paper's lead author and an Assistant Professor of Global Health at IHME.
"Over the past decade, numerous interventions have been evaluated, but very little evidence exists about their long-term effectiveness,” Afshin said “Over the next 10 years, we will work closely with the FAO in monitoring and evaluating the progress of countries in controlling overweight and obesity. Moreover, we will share data and findings with scientists, policymakers, and other stakeholders seeking evidence-based strategies to address this problem."