Don't jump the diet gun

Obesity among Americans is a two-pronged problem: Approximately a third of the nation's population falls into the obese category, and many of these obese individuals are on diets that don't work.

Two stories on the same day last week reported on these two problems. One story, based on RAND Corp. research, shows Americans are getting bigger at an alarming rate. The research underscores common sense that says we live in a society where food -- not all of it good for us -- is plentiful and where less physical activity is required to survive, thanks to mechanization and other labor-saving advancements.

The other story, though, probably caught the most attention. It reported the results of a controlled study of low-carbohydrate diets conducted by a researcher at the Harvard School of Public Health. This is the study that indicates dieters on low-carb diets can consume more calories that individuals on low-fat diets and still lose as much or more weight.

This research bolsters those who have claimed for years that low-carb diets -- like the one best-known for its developer, Dr. Robert Atkins -- result in weight loss regardless of the amount of calories consumed. Most scientists contend that, in order to lose weight, a dieter has to consume fewer calories that are used up. The rule of thumb has been that approximately 3,000 calories are equal to a pound of weight. So, the scientists said, anyone eating 4,000 calories a day but only using up 3,000 calories a day through metabolism and physical activity would gain about 2 pounds a week.

But adherents of the Atkins diet and other low-carb diets have insisted that they could eat as much as they wanted and still lose weight. The Harvard study indicates they are right.

Atkins dieters are known for eating large quantities of food that any prudent mother might choose to steer her family away from. Low-carb dieters gobble up just about anything with few or no carbohydrates, including fried eggs, cheese and red meat (including fried bacon).

In addition to defying the calories in-calories out thinking that has regulated diets for decades, the low-carb diets also seem to fly in the face of medical authorities concerned about increased cholesterol and the diseases it causes.

So have all those doctors pooh-poohing the Atkins diet been wrong? The Harvard study's results surprised just about everyone. And the study hasn't explained why the low-carb approach works without counting calories.

Something else about the study may come as less-welcome news. Low-carb meals for the Harvard study were prepared by a restaurant, which meant the participants in the study were not left to their own devices when it came to choosing what to eat. Moreover, the restaurant-prepared meals consisted mainly of fish, chicken, salads, vegetables and unsaturated oils -- all sensible meals on any diet. No 20-ounce steaks. No plates full of fried bacon. No cheese.