People often hear or talk about stress-eating. This is observed when people deliberately consume a lot more food than needed in order to pacify the stress that they are going through. However, weight gain because of stress is found to be no longer just a matter of hearsay.
A recent study has proven that people that take high-calorie food while under stress actually gain more weight than those who consume the same food but are not under stress.
The scientists explained that a molecular pathway in the brain which is controlled by insulin drives the additional weight gain for a person who is under stress.
Herbert Herzog, the head of the Eating Disorders Laboratory at the Garvan Institute of Medical Research, pointed out that people should be much more conscious about what they decide to eat, especially when they are stressed out. Taking time to think about the diet or the food to consume can avoid the fast development of obesity.
According to the research, the center of weight gain is s molecule called NPY, produced by the brain naturally in response to stress. This molecule stimulates the urge to eat. For their research, the scientists observed the occurrence of this molecule in mice.
Kenny Chi Kin Ip, the lead author for the study and one of the researchers in Herzog's laboratory, explains that when his team eliminated the production of NPY in the amygdala, the occurrence of weight gain was also reduced. This means that without NPY, the weight gain on a high-fat diet when under stress is the same weight gain seen when the same high-fat diet is taken in a stress-free environment.
The team further explained that the food intake is mainly controlled by a part of the brain called the hypothalamus. This part of the brain works hand-in-hand with the amygdala which processes emotional responses.
The normal process involves the production of insulin after a meal which sends a signal to the hypothalamus telling the body to stop eating. However, in this research, the scientists found that the nerve cells which produced NPY in the amygdala had receptors for insulin.
By observing mice, the team of scientists has discovered that chronic stress alone raises blood insulin levels slightly. If it is combined with a high-calorie diet, the insulin levels would be raised to 10 times higher (in mice).
The scientists explained that the prolonged high levels of Insulin in the amygdala would cause the nerve cells to become insensitive to insulin. This will then put a stop at detecting the insulin, and in turn, would fail to give a prompt for the body to stop food consumption.
