Anatomy of a Potbelly

By Anjula Razdan, Experience Life

Summer might be over, but don’t let your waistline go to the dogs just yet. Looking good at the beach isn’t the only reason to flatten our tummies. Recent studies in fat distribution are giving us an even more pressing incentive to reduce our rounding stomachs: our health.

It turns out that abdominal fat (more so than fat in other areas of the body) has a major impact on whether we stay healthy and vital or put ourselves at increased risk for several chronic diseases.

First off, we’re not talking about your typical tummy fat, so don’t fret about a little paunch. All of us need a bit of internal belly fat, says nutritional expert Pamela Peeke, MD, MPH. “We need stomach fat to help cushion organs, maintain internal body temperature, and it’s also a good source of backup fuel,” says Peeke, author of Body for Life for Women: A Woman’s Plan for Physical and Mental Transformation (Rodale, 2005) and Fight Fat After Forty (Penguin, 2000).

The problem is that not all abdominal fat is created equal. It is the type of belly fat -and the places it’s located- that determine whether it’s likely to lead to health problems.

Two Types of Fat
Ringing all our midsections are two different kinds of fat: subcutaneous and visceral. Subcutaneous, which means “under the skin,” is the fat we can see and pinch the jiggly stuff most of us lament in our bathroom mirrors. But, surprisingly, we need to worry less about subcutaneous fat than we do the visceral stuff.

Visceral, which means “pertaining to the soft organs in the abdomen,” is the fat stored deep in our abdomens around the intestines, kidneys, pancreas and liver. This is the stuff that tends to make our tummies protrude in classic “beer belly” fashion.

While visceral fat and subcutaneous fat look much the same from a surgeon’s point of view (they have the same consistency and yellowish color), they look different under a microscope, and they function very differently on a biological level.

Subcutaneous fat is often described as a “passive” fat because it functions primarily as a storage repository. It requires a fair bit of metabolic intervention from other body systems and glands in order to be processed for energy. Visceral fat, by contrast, is considered very “active” because it functions much like a gland itself: It is programmed to break down and release fatty acids and other hormonal substances that are then directly metabolized by the liver.

When the fatty acids that are produced in our abdominal organs go directly to the liver, it “produces an unfavorable metabolic environment and triggers the liver to do all sorts of bad things,” says health expert Marie Savard, MD, author, with Carol Svec, of the recent book The Body Shape Solution to Weight Loss and Wellness: The Apples and Pears Approach to Losing Weight, Living Longer and Feeling Healthier (Atria, 2006). “Excess visceral fat can lead to increased blood sugar and higher insulin levels, and it also generates increased inflammation, all of which are the perfect set-up for diabetes, certain types of cancers and stroke.”

Abdominal obesity is a key risk factor for insulin resistance and “metabolic syndrome.” The chronic inflammation that results from excessive visceral fat has also been linked to heart disease, and a recent Kaiser Permanente study of 6,700 participants showed that people with higher rates of abdominal fat are 145 percent more likely to develop dementia.

Visceral fat may be located in our abdomens, Peeke says, but it can wreak all sorts of damage that goes far beyond our bellies. “No other fat in the body does that,” she says. Which is precisely why we need to keep the amount of fat in our abdomens under control.

When we don’t, the result may be a belly that’s literally packed with fat, a phenomenon that can lead to a surprisingly solid protrusion one with deceptively little pinchable fat on the surface.

Carrying excess visceral fat “is like trying to pack 7 to 10 pounds of potatoes in a 5-pound bag,” says Silver Spring, Md. based bariatric surgeon Gary C. Harrington, MD. “There’s no more room for things to grow in there, so it becomes very tight.”