The levels of obesity in the world are reaching epidemic proportions, a fact that should not be surprising to anyone. The rise in the availability of fast, unhealthy foods and the undesirability of exercise is making it tough for people to live healthy lifestyles. But, what if there is more going on inside of your body than the simple fact that unhealthy eating and exercising are out of proportion?
The science suggests that there is slightly more going on with how your body breaks food down and the role that the brain plays in it, a process that could be key to understanding and fixing the obesity epidemic. The key to understanding the science is understanding the role that insulin plays.
It is well documented that an increase in obesity leads to higher risks for developing type 2 diabetes. Type 2 diabetes is characterized by too much glucose in the blood. Initially, obese patients see an increase in their insulin blood levels in reaction to high levels of glucose. Over time, the body cells become resistant and no longer can use insulin in the way that they should. Thus, the body has too much glucose, or energy molecules, in the blood, but no way to use this energy.
The brain also has insulin receptors. It has been shown that when insulin binds to insulin receptors in the brain, it effects neurons that are in charge of sending signals to the rest of the body to either eat food or not eat food. POMC neurons tell the body that it is full and that it should increase energy expenditure. AgRP/NPY neurons on the other hand tell the body that it needs more food and that it should decrease energy expenditure.
Insulin also binds to and causes changes in the part of the brain where food intake and energy expenditure are controlled, it also binds in the part of the brain that controls the reward system. Insulin is able to increase the levels of dopamine, the brains reward chemical, when it binds in the brain.
Through its many actions in the brain, insulin can increase and contribute to the development of obesity. The future of obesity research will continue to look into insulin and it’s role in brain modulation during obesity, but for now it is clear that obesity is more than a disease of lack of lack of control, and instead has a major brain component.
More information about Type 2 Diabetes can be found here
Information for this blog was found here
Image in blog can be found here