Mild Stress Could Lead to Weight Loss

Saturday, February 13rd, 2016

According to a new study, mild psychological stress could cause weight loss by activating brown fat. The study was conducted by the University of Nottingham’s School of Medicine and could lead to effective new treatments for type 2 diabetes.

There are two types of fat found in the human body – brown fat and white fat. White fat is more common and used to store excess calories. It is considered a health risk if a person has high levels of white fat, whereas high levels of brown fat are thought to be healthier.

Brown fat generates heat by burning calories and it was previously thought that it could only be found in hibernating mammals and human babies. Only recently has it been discovered that brown fat can be found in human adults as well. People who have higher levels of brown fat tend to have lower levels of white fat and a lower BMI than people who have low brown fat levels.

In order to burn calories, brown fat must be activated first. Studies from the past have suggested that cooler temperatures activate brown fat and it is thought that if scientists can find a way to increase levels and activate brown fat, it could be an effective obesity treatment. A reduction in obesity levels could prevent a number of type 2 diabetes cases.

The study, published in Experimental Physiology, was carried out on five female subjects and found that brown fat activity was activated by mild psychological stress. The participants first had to take a short mathematics test before watching a relaxation video. The researchers used infrared thermography to measure the temperature of skin on the neck, as this is the main area of brown fat. They discovered that activity levels of brown fat were significantly higher when the levels of cortisol were raised. This was when the participants were stressed before the mathematics test.

As the study only involved five participants, further studies of a larger scale will be necessary to validate the conclusions of this study. Nonetheless, the research has added an interesting dimension to the promising subject of brown fat.

Professor Michael E Symonds, co-author of the study, said that the research shows the variation in brown fat activity between participants could be explained by differences in their response to psychological stress. He said this is significant because brown fat has a unique capacity to metabolise glucose and generate heat rapidly.

According to Professor Symonds, most adults have between 50-100g of brown fat, however due to its capacity to generate heat being 300 times greater than any other tissue per unit mass, it could potentially metabolise lipids and glucose rapidly. There is a contrary relationship between BMI and brown fat levels and whether having more active fat is a direct consequence has not yet been established fully.

Professor Symonds went on to say that having a higher understanding of the core factors that control brown fat activity, for example exercise and diet, has the potential to bring in sustainable methods to prevent diabetes and obesity. Alongside environmental and/or dietary interventions, new techniques to induce mild stress to promote brown fat activity could be incorporated. This would possibly contrast with the negative impact of more severe and chronic stress that can contribute to poor metabolic health.