Last week I wrote about the similarities between grey matter decline of those who are obese and Alzheimer’s disease patients. This past week I was reading more information about how obesity affects the brain’s ability to properly process sugar, based on a study at Western Michigan University, which involved obesity-prone rat models.
This time I wanted to continue to dive deeper into how the brain is negatively impacted by overeating and obesity and to take the emphasis off the body for a change. Not much attention is being given into the fact that obesity, especially in this country, is at epidemic proportions. Our culture seems to set the stage. Look at how many hours we spend on our mobile phones. How convenient it is to buy low nutritional grade food from countless fast-food restaurants. When we should be spending more time in the gym or outside being active.
Obesity is a multi-system condition for the body. Because it negatively impacts many different areas, including our brain.
Scientists have looked into the reason why we overeat and have determined it revolves around one particular brain structure: the nucleus accumbens. This area is the motivation center of the brain. It drives reward-seeking behaviors like food, sex, nicotine, alcohol and other recreational drugs. This area for motivation is essential for our species survival.
Carrie Ferrario Ph.D., associate professor in the Department of Pharmacology at U-M Medical School said, “ What was advantageous when food was hard to find has become a disadvantage and unhealthy in the current food dense environment. This is compounded by the over-abundance of over-processed, low nutrition foods that may satisfy out taste but leave our bodies unnourished.” She added, “People don’t tend to find it difficult to turn down an extra serving of broccoli, but just one more french-fry or making room for a bit of chocolate dessert… that’s a different story. The real challenge is overcoming these urges and changing our behavior when it comes to food.”
The scientific research team of this study wanted to pinpoint the differences the nucleus accumbens had in obesity-prone rats and those who were obesity-resistant. Seeing how data showed an immense toll obesity had on all the major systems of the body.
What they did was to take a look at what was happening in the brain in real time while processing glucose (type of sugar) by adding a tracer to it, so they could track it. This way it allowed them to see how fast or slow the sugar was metabolized by the obese rats and those who weren’t.
Sugar is the main source of fuel for the brain. The sugar molecule is broken down into other molecules like, glutamate (an excitatory neurotransmitter), GABA (an inhibitory neurotransmitter) and glutamine. These molecules are important at influencing the activation of neurons to speed up or slow down areas in the brain and nervous system.
They found out that sugar was being processed and broken down slower by the obese rat models. This meant that it took longer for the glucose to get consumed into the nucleus accumbens. When they measured the concentration levels of the glutamate, glutamine and GABA they found there was an abundance of glutamate remaining within the synapse. Indicating the brain was having a “defective neurotransmitter recycling response” to the sugar. Normally this critical balance is maintained by astrocytes.
Astrocytes are star-shaped cells that outnumber neurons about 10:1. One of their jobs is to support the neurons by pulling the glutamate out from the gap between the neurons or (the synapse) and convert it into glutamine. Then send it back to neurons to be used as glutamate (excitatory) or GABA (inhibitory) neurotransmitters. Meaning to turn on or turn off neurons they are communicating with. The delicate balance between these two neurotransmitter types has a profound effect on our brain’s ability to properly perform.
The results of this study give reasons to suggest a cause and effect relationship diet may have in how and why certain people are prone to obesity. It also singles out the critical defective mechanism within the nucleus accumbens as a main cause.
What and how much we eat is surely a large part of getting to the bottom of why we become obese. But the structure of our brain influences how differently it performs from one person to another. By knowing this fact, we are better equipped to make smarter choices that will ultimately create a healthier life.
-A Balanced Brain is a Better Brain for a Happier Life-