Fat: it doesn't just sit there

Philip J. Goscienski, M.D.

October 2005

At various times in history and among different cultures people have admired, condemned, honored and tolerated fatness. Except for the medical community most of us seem to be indifferent about it. After all, more than two thirds of Americans are overweight, a third are frankly obese and about 5 percent are morbidly obese, weighing 100 pounds more than nature intended.

The extra fat that so many of us carry around isn't all bad. First of all, it's a source of energy when food gets scarce. Not that it matters much in developed nations. Most Americans never miss a meal and we only know famine from news reports.

Fat helps us to tolerate cold, which makes me wonder why Scandinavians are such a slender lot.

Like it or not, a woman's curves are due to fat. She also finds it hard to get rid of but that's an evolutionary adaptation that I'll save for another column. As a girl enters adolescence she needs a minimum amount of body fat to allow her to become sexually mature and ready to have children.

About 15 years ago scientists began to realize that our accumulations of fat are not just inert collections of calories that we haven't burned off. Fat cells, known as adipocytes, manufacture dozens of chemicals that we need in order to function normally and others that lead to or accelerate diseases such as diabetes and cancer.

Fat cells produce leptin, a substance that was thought to be the key to controlling obesity but which fell far short of that. Injecting leptin into rats works to control obesity but humans don't respond the way rats do. That might help to explain why fat rats are rare but fat humans are not.

The downside of fat tissue as a chemical factory is that it produces substances that promote inflammation, diabetes and heart disease. Although that seems like a strong negative, understanding how these chemicals work could eventually lead to new treatments for these diseases.

Anyone who hasn't just arrived from another planet knows that stem cells are a hot topic in the news. Research into stem cells is still in its earliest stages but it's having an effect in politics, finance and religion. The finding that fat tissue is literally loaded with stem cells is roiling the waters in all these areas. Fat cells themselves don't revert back to stem cells, but within fatty tissue there are surprisingly large numbers of adult stem cells. Laboratory studies have already shown that these cells have the potential to become cartilage, muscle, bone and nerve tissue.

There are stem cells in other parts of the body too, especially in the bone marrow but fat is obviously accessible, to say nothing of plentiful.

It may be years, if ever, before fat-derived stem cells will be the cure for Alzheimer's disease, stop the progress of diabetes, grow new heart muscle or restore damaged spinal cords. However slim the chances of such exciting cures, workers in the field are already figuring out how we can bank our own fat tissue so that we'll have compatible stem cells when we need them to rebuild diseased or damaged body parts.

It's about time that fat got a little respect.

Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at drphil@stoneagedoc.com.