Which Diet is Best? The One That Works for You

Gather together some diners who are trying to lose weight, then sit back and listen to the debate.

Almost anyone who's on a diet -- or at least one that's working -- is convinced his or her plan is the best. One will swear by low-carb plans, such as Atkins; another will say low-fat is the way to go.

"People get tied in to a specific diet," said Lona Sandon, an assistant professor of clinical nutrition at the University of Texas Southwestern Medical Center at Dallas and a spokeswoman for the American Dietetic Association. "It's almost territorial. How dare you step on their diet?"

With nearly two-thirds of U.S. adults deemed overweight, the question about which diet is best won't disappear soon.

But Sandon and other weight-loss experts have some news for quibbling dieters: The right weight-loss plan for you is the one that works. And you can stay with it as long as it's nutritionally sound.

Many types of diets can work in terms of helping you shed pounds, said Dr. David Schteingart, associate director of the General Clinical Research Center at the University of Michigan Health System.

But there are benefits and drawbacks to the popular plans, he and Sandon agreed, depending on how each works. Knowing those pros and cons can help you decide your best weight-loss path.

With a low-carb diet, Schteingart said, "essentially what it does, and why it works, is that you are also reducing your calories. But because it is low in carbohydrates and high in protein and fat, you feel less hungry so compliance to the diet is much greater than to a high-carb diet."

Limiting carbohydrates can also reduce insulin production, Schteingart said. This can be important to people with weight problems who are prone to a condition called metabolic syndrome, which can lead to diabetes, he said.

"Low-carb diets tend to decrease insulin levels and increase insulin sensitivity," which is good, Schteingart said.

But there are downsides to limiting carbohydrates, Schteingart said. People on such diets tend to feel tired because they lack the quick source of energy provided by carbohydrate-rich foods such as bread and pasta and fruits such as apples and bananas.

Low-fat diets, on the other hand, automatically limit calories because each gram of fat has 9 calories, compared to just 4 calories for each gram of protein or carbohydrate. But low-fat, high-carb plans tend to make you feel less satisfied, according to Schteingart, and dieters on these plans complain of hunger.

Following a low-fat plan does reduce cardiovascular disease risk, Schteingart said, because it can lower blood cholesterol levels.

But two studies, published in May 2003 in the New England Journal of Medicine, found the Atkins approach doesn't boost cholesterol levels, as you might expect.

For his overweight patients, Schteingart usually prescribes a diet somewhere between a high-carb and a high-fat, high-protein plan. He urges dieters to check with a physician, a dietitian or both, so an eating plan can be tailored to individual needs.

Sandon tells her dieters to focus less on the type of plan and more on the basics, such as calorie control.

"Anytime you have calorie reduction, now matter how small or large, you will see weight reduction," she said, although that weight loss may take some time. It's also a good idea to get more physical activity -- with your doctor's OK, she said.

Sandon tells dieters, whether they are high-carb or low-carb fans, to begin by cutting portion sizes. She also cautions against eliminating too many carbohydrates.

She advises eating 30 grams of carbs -- or about two servings of carb-rich foods -- at each meal. For lunch, that could be as simple as having two slices of bread, Sandon said. (On many low-carb plans, 60 grams of carbohydrates a day are suggested as the maximum allowed during the weight-loss phase.)

The bottom line, Sandon and Schteingart agree, is that people need to limit their consumption of calories.

"People have to change the way they eat," Schteingart said. "This has to be done on an ongoing basis."

Or, as most overweight Americans know, the weight will come right back.