Dear Lynn:

I am having trouble reconciling a low-carb eating plan with the food pyramid. Weight-management physicians prescribe low-carb diets; however, I am concerned about further slowing my already-damaged metabolism by trying yet another "method" to lose weight. I admit I feel better after a week of less simple sugar and white flour. I would appreciate any medical evidence of the soundness of this eating plan and how this is associated with the concept that obesity may be related to hyperinsulinemia. Does cutting back on carbs promote fat burning? I do not have diabetes, nor do I suspect too much insulin. Should I try this or get back to the pyramid?

--BirdE

Dear BirdE:

There isn't any scientific evidence that eating a low-carbohydrate diet promotes weight loss or that having high insulin levels promotes weight gain. The weight-loss gurus are extrapolating from people with Type 2 diabetes, where high levels of insulin do promote deposit of fat and therefore weight gain, but it's not as simple as the diet books make it out to be.

The key to weight loss has always been eating fewer total calories than we use. You can do that by following the food pyramid or a low-carb plan. If your basic idea is to eat less simple sugars (sugar honey, candy, cookies) and highly processed foods that contain white flour (most crackers, pasta, white rice, many breads), then you can still follow the food pyramid. Just choose less-processed-grain foods such as brown rice, whole-grain cereals (Cheerios is an example) and bread made from a whole grain. Keeping your simple-sugar intake low is encouraged on the food pyramid; those foods are found in the top or "extra" section.

You're right to be concerned about your metabolism. Keep it as high as possible by exercising (including both aerobic and weight training activities) and not cutting your calorie intake too low, generally not below 1,200 calories for women (and many experts believe 1,500 calories is even better). Try to eat a variety of foods, focus on less-processed foods, choose lean sources of protein, and try to figure out when you know you've had enough to eat. It's not simple to do, but the end results are definitely worth it.

Lynn Grieger, R.D., C.D.E.

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