Top Causes of Belly Fat

Farris Russell and obesity researcher and physician, Per Marin, M.D., Ph.D authored the book "The Potbelly Syndrome." In this book, the researchers discuss the development of a potbelly and outline the major contributors, namely high cortisol from chronic stress and the high insulin that leads to insulin resistance and type 2 diabetes. The authors connect high cortisol levels to insulin resistance, although the two can exist independently. Russell notes four stages of potbelly development. Ultimately, the excess blood sugar that results from either high cortisol or high insulin levels is seldom used by the cells of the body and is deposited in the abdominal area as fat.

Stress

The stress response in an industrialized world can be viewed as a necessary evil. In modern times stress is not an acute event, triggered by the immediate need to preserve life in the face of a dangerous predatory animal. Instead, stress is a chronic condition--it has even become an "occupational illness" in our society, notes the U.S. Department of Labor article on "Occupational Stress." The stress response leads to increases in the hormone cortisol. While acute increases in cortisol may save life under dangerous circumstances, chronically high cortisol levels are detrimental to the body. In 2001 "Science" article, researchers Hiroaki Masuzaki and Jeffrey Flier determined that abdominal fat in particular expressed high amounts of the enzyme that converts precursors of cortisol into its active form. With this original research in genetically-engineered mice, the belly fat-cortisol connection was made.

Insulin Resistance

Farris and Marin state that most people with high cortisol will have insulin resistance, and many of those with insulin resistance will have pot-belly syndrome. Insulin resistance, as an isolated event, occurs from an unmet need for constant insulin production by the pancreas. In insulin resistance the body produces enough insulin but does not use it properly. When blood sugar rises after a meal, insulin should transport the glucose to the cells to be burned for energy. The National Diabetes Information Clearinghouse states that when the insulin is defective, blood glucose levels remain high, setting the stage for diabetes. Farris and Marin note that when glucose builds up the in bloodstream, it will be stored in the abdominal area as fat.

Menopause

As some women approach menopause, they complain that their body shape is changing. They may move from the pear-shape, where fat is deposited to the estrogen-sensitive areas of the body like the breasts and hips, to an apple-shape. The apple-shape was noted in the 1999 "Applied Nutritional Science Reports", by Joseph Mayo, M.D., as truncal obesity. During the reproductive years, the ovaries produce the majority of the estrogen in the body. However, the authors state, that once menopause occurs the adrenal glands and fat cells take over as primary producers of both estrogen and testosterone. The increasing reliance of the adrenal glands for sex hormone production can also stimulate increased cortisol production and abdominal fat deposition. Furthermore, the loss of the feminizing hormone-estrogen, makes women develop the more android, male-pattern fat distribution of the apple shape. Robert Eckel notes these findings on page 352 of his text, "Obesity: Mechanisms and Clinical Management."