There has been a significant rise in the cases of obesity in the developed world. There is a certain behaviors like increased portion size, sedentary lifestyle with almost no physical activity, etc., that promote obesity. For years, scientists and researchers have known that there is a connection between stress and obesity and recent researchers have found evidence that supports the connection. There are certain biochemical reactions that explain the connection. The sooner doctors are able to understand them in details; they will be able to address the problem of obesity that is burgeoning in the developed world.
A new study by the Brandeis University states that people who are overweight are at a greater risk of stress-related diseases like type 2 diabetes, cardiovascular diseases and also cancer. When a person is under psychological stress, it can trigger biological responses in their body that are similar to the effects of illness or injury, including inflammation. When we get injured, inflammation is a necessary step for the healing process. But, inflammation that is caused due to stress can be a major contributor of chronic and life-threatening diseases.
In a research paper that was recently published in Brain, Behavior and Immunity, Brandeis researchers made the observation that stress-induced inflammation is significantly higher in overweight and obese individuals in comparison of individuals who have healthy weight.
Nicolas Rohleder, psychology professor and the study’s principal investigator, stated that it has been known for quite a while that overweight and obese individuals have chronic and low grade inflammation. But, what is interesting to note that when you add stress to the mix, the hazard is almost double.
The paper was co-authored by graduate student Christine McInnis, with fellow doctoral candidates Danielle Gianferante, Luke Hanlin, and Xuejie Chen, as well as co-investigators Myriam Thoma, Juliana Breines, and Suzi Hong.
For this study, the inflammation levels due to interleukin-6 (IL-6), an inflammatory agent linked to stress, were measured in normal-weight and overweight individuals. The participants were made to undergo two psychological stress tests. The normal-weight and overweight individuals were classified after taking into account various factors like body mass index (BMI) and body fat percentage. Individuals who had a BMI of 25 or higher were classified as overweight.
On the first day of testing, it was noted that lean and overweight individuals reacted similarly to stress, despite the fact that overweight participants had a higher starting levels of IL-6. The second day test results were however different. On 2nd day, the IL-6 levels of overweight participants nearly doubled, while the levels of lean participants remained the same as on the first day.
An important observation made by McInnis and Rohleder was that relationship between BMI and IL-6 levels was linearthe higher the BMI, even among lean individuals, the higher was the IL-6. McInnis said that it showed that every percentage point of body fat increases the risk of inflammation.
When people are stressed they tend to eat inappropriately which results in unnecessary weight gain that in turn causes more stress. About 2/3rd of Americans are overweight and the obesity rate worldwide is doubling since 1980. It is very crucial to understand the health risk associated with obesity and with this research we are a step closer to understanding the same.