Once Hungry, Forever Eating: The Neurological Impacts Of Poor Diet On Obesity

The Obesity Problem

According to the CDC, more than 1/3 of adults in the U.S. are obese. Why is this a problem? Why is obesity rising? Could we blame it on America’s fast-paced society and the growth of processed and fast foods? Sure we could, and those factors do play a role to some extent. Are people just not making conscious healthy decisions anymore? Of course not everyone makes healthy conscious decisions, but can we attribute that solely to the will of that individual? What if some people are not actually controlling their unhealthy decisions? What if their brain has been rewired in a way to promote their actions of unhealthy eating?

I hope you are not surprised when I say YES, scientists have been discovering that brain rewiring may be a huge factor in the obesity epidemic we have not yet considered.

Watching the Hips, Watching the Brain

Saturated fatty acids and other unhealthy components of processed food commonly consumed today pose a danger to the chemical signaling within our brain. These molecules are able to freely cross and accumulate within the brain tissue, leading to the activation of various inflammatory pathways within the brain. Over time, this over-activation of inflammatory pathways in the brain leads to insulin resistance and the inability of the body to properly utilize insulin for energy homeostasis maintenance. So my choice of chips over carrots at the grocery store is not only going to my hips, but is also negatively changing the chemical signaling within my brain that is responsible for regulating my energy and food intake. Awesome..

Obesity and Type 2 Diabetes

Insulin normally plays a role in the body to help store sugars (glucose) in the cells of the body after food consumption. This allows body cells to use that stored glucose for the body’s energy production of ATP, which powers our physical and mental actions, allowing us to go about our daily functioning. Diets high in sugar and simple carbohydrates (or simply just a high caloric diet) lead to insulin resistance because of the excess insulin released when you eat a lot of high-calorie foods. When too much food is consumed (high fat diet), the organelles in your cells become overwhelmed and stressed and inflammation ensues. The resulting activation of inflammatory pathways in the brain then lead to the inhibition of insulin receptors on body cells and ultimately insulin resistance. So, now when food is consumed, the body continues to release insulin, but the insulin receptors on body cells no longer respond to insulin’s binding, and glucose remains in the blood instead of being stored in body cells. Increased blood glucose levels over time is harmful to the body. This is also known as Type 2 Diabetes.

Insulin resistance also leads to the inhibition of POMC neurons in our body. This is of great concern because POMC neurons in our body are normally activated after food intake and tell us to stop eating. Inhibition of POMC neurons leads to the overeating often associated with obesity. Normally when we are hungry, AgRP neurons are activated that tell us to start eating so that we can gain more energy. The activation and inhibition of POMC and AgRP neurons are a vital component of our body’s ability to maintain energy homeostasis. Scientists have found an increased ratio of AgRP:POMC neurons in the brain of obese individuals, as well as an up regulation of inflammatory pathways discussed above.

Obesity is in the brain.

Finals week, Stress Eat

STRESS EATING IS REAL PEOPLE. And SURPRISE, it originates in the brain. So this is why I gain 5 pounds during finals week. When your body is stressed and then food is consumed, insulin is released and it increases the firing rate of dopamine neurons. The dopamine neurons then release a lot of dopamine, which is the molecule responsible for the reward pathway and the brain’s ability to make us experience “pleasure.” This is why you feel happy and satisfied after eating something yummy during finals week, like pizza. Over time, the brain starts to remember how satisfied you feel after stress eating, because your brain lays down information and forms memories more when the body is under stress. The next time you are under stress, the brain’s memory station, the hippocampus, and the reward system in the brain activate and have the ability to override any other signaling in the brain responsible for maintaining energy homeostasis. This is why we tend to stress eat, even when we are not hungry! So this brings up the question of whether or not people are actually responsible for the unhealthy decisions they make.

What do you think?

Goodbye Leptin, Hello Hunger

Normally leptin serves the function of telling the brain that it is not hungry and does not need any more food. However, as one consumes more food, body fat accumulates and leptin concentration increases in fat cells throughout the body. This disrupts proper leptin signaling and prevents leptin from telling the brain that it is not hungry anymore. Thus, the brain thinks it is starving, leading to increased food consumption and further body fat accumulation. This pathway continues to spiral out of control unless diet is altered.

Holiday Tips

With Christmas quickly approaching, one can only help but look forward to of all of the goodies to be eaten throughout the holiday season. I mean, you cannot resist eating all of the yummy food at family Christmas meals, right? Take into consideration these few tips to help you and your loved ones to stay ON TRACK this holiday season:

Keep in mind the holiday season is about BEING WITH FAMILY, not eating food
Suggest bringing a healthier dish to meals (sweet mashed potatoes verses mashed potatoes)
Help yourself to the yummy food of the holiday season, but in MODERATION (get your fruits in with breakfast and make sure vegetables have a place on your dinner plate)
Have ONE cookie instead of FIVE cookies
Drink 16 ounces of water before each meal (it will help you feel fuller and decrease your food intake)
Get your daily workouts in (walk the dogs, family walk after dinner, family gym session)
Take this time to CATCH UP on SLEEP