Q. Thank you for your informative article on cellulite. However, I remain somewhat confused. How do you explain the dimples and ripples that appear on the thighs and buttocks of those people who appear to be slim? There are also many large overweight people with thighs and buttocks that are smooth and ripple-free.

L.C.

A. I've received several letters regarding the cellulite column. For those that missed it, I said there's no such thing as cellulite. Any dimpling caused by fat under the skin is just that, fat.

You brought up three good points. Why do some fat people have smooth skin and some fat people have the dimpled look? And why do some rather skinny people have that dimpled look?

Our genes dictate how and where we store our fat. If you're looking for an interesting book on the subject, try Anne Scott Bellers' "Fat & Thin: A Natural History of Obesity," Farrar, Straus and Giroux.

Women tend to store more fat in the hips and thighs, while men store more in the midsection. If we randomly selected 20 men and women, we'd probably find that each stores his or her fat a little differently. These are the inherited traits I was talking about.

If we observed just the bellies on the men, we'd see different shapes to their midsections. One might have a hard, protruding, well-shaped blimp belly. You've seen the type. Their belly sticks out so far that they have to lean backwards to keep from falling forward. Yet the belly feels quite firm.

Then there's the tire-tube belly. This guy has a circle of fat at the bellybutton level. There's also the cellar belly. This guy carries the majority of his fat just below the belt line. The dunlap belly is the one where the guy's belly done laps over his belt.

The group of 20 women would have different looks but equally individual traits -- all of them inherited characteristics.

As you pointed out, it's possible for a fat person to have undimpled skin, and that's certainly an inherited trait. The thickness and elasticity of the skin, and the manner in which the fat is stored may determine that look. So, if you're fat with undimpled skin, you can probably thank your parents for the lack of dimples.

What about the person who's not overweight, yet has the dimpled look? There are three possible reasons.

Genetics is one. It's possible for the in-shape female, for example, to have the dimpled look if she inherited those specific traits that cause the skin to dimple. Another possibility is that the person had been fat and out of shape, and the once- stretched skin dimpled after the weight loss. Muscle atrophy is another cause for dimpling. Typically, the older we grow, the less active we become. This inactivity will cause muscles, especially those big and powerful muscles of the buttocks and thighs to shrink. As the muscles shrink, the skin begins to dimple. It's like letting the air out of a balloon.

The key to preventing dimpling? Don't add any excess weight, exercise the muscles of the buttocks and thighs, and hope you haven't inherited the genes that cause the dimpling effect. If you already have dimples, lose any excess fat and exercise the muscles involved.

Don't blame those dimples on cellulite. It doesn't exist. Don't write off your excess fat as cellulite. Some people continue to believe in cellulite rather than face the facts. Those same people are probably asking Santa for one of those sweat belts to lose weight. Ho, ho, ho!