There’s More to Weight than What We Eat

Published in NSIDE M.D., San Antonio Medical Journal

Losing weight can be perplexing and frustrating. While some people struggle with weight gain throughout their lives, many individuals find they have trouble keeping the pounds off as the years go by. Even though they eat less than before, they still gain weight.

There are healthy, smart ways to lose weight, and keep it off, that begin with understading why people gain weight.

Weight gain is the result of an imbalance between calories consumed and calories used. Behavior, environment and genetics can contribute to the imbalance. Caloric balance is maintained within the body by chemical messengers known as neurotransmitters and hormones that help the body store and break down fat to meet the body’s daily energy needs. When this system of chemical messengers fails to function, the appetite says to eat more even though the individual should feel full.

In addition, environmental and biological factors including stress, poor diet, neurotoxins and genetics can cause imbalances in the levels of neurotransmitter chemicals in the brain. These imbalances can trigger or exacerbate weight control issues.

Neurotransmitters are chemicals that relay signals between nerve cells called neurons. They are present throughout the body to maintain proper brain and body functions. An example is serotonin, a neurotransmitter that regulates mood, hunger and eating behavior. When serotonin levels are low, one may experience excessive hunger, frequent carbohydrate cravings, and feel irritable, moody or depressed.

For some people, being overweight is related to low serotonin levels, but balancing neurotransmitters is just one piece of the weight-gain puzzle. Stress also causes weight issues because it aggravates the pancreas and adrenal glands, and interferes with the regulation of blood sugar.

Stress is another key cause of weight gain. The stress response, best known as “fight or flight,” involves the secretion of stress hormones from the adrenal glands. These hormones, including epinephrine, norepinephrine, glucocorticoids and mineral corticoids, prepare the body for physical danger in a number of ways: nervous system activity increases, heart rate and blood pressure rise, surface blood vessels constrict allowing for increased blood flow to the vital organs, and the liver releases stored glycogen to increase blood sugar.

Cortisol is the primary adrenal hormone responsible for changes in blood sugar metabolism and insulin activity. Cortisol decreases insulin sensitivity by receptor cells and glucose uptake and increases blood sugar. The rise in blood sugar serves as a reservoir for the central nervous system, which requires a continuous supply of glucose to function.

When stress is high, cortisol levels rise, insulin resistance climbs, hyperinsulinemia intensifies, and as a result, the body gains weight. Simply put, stress causes weight gain.

Many serious chronic conditions are associated with neurotransmitter and cortisol deregulation. One of the more serious is Type 2 diabetes and its complicating factors. The inability to lower blood sugar in people with Type 2 diabetes can cause impaired insulin secretion, hyperinsulinemia, insulin resistance, impaired glucose tolerance and increased glucose production by the liver. Consequently, the pancreas can no longer function properly because the body’s communication network breaks down.

By looking at the factors that cause stress, individuals can focus on balancing these systems in the body and thus create an environment for weight loss and increased well-being.

Because every individual is biologically unique, one size does not fit all. It is important to look beyond the obvious weight-loss and stress-reduction methods, including exercise, education and diet, which also are important. Weight loss is a complex issue with many variables that fluctuate with each body. In the end, neurotransmitter function, cortisol levels, portion-controlled low-carbohydrate diets and individually tailored exercise programs can produce remarkable changes in a person’s health.

By Kay Spears, San Antonio Nutritionist

Published in NSIDE M.D., San Antonio Medical Journal

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