Doctors weigh benefits and possible long-term effects of low-carb diets

HAMILTON, Ohio -- It's everywhere. In the grocery aisles. At the restaurants and fast-food joints. And it will have you wondering where the pizza dough and burger buns went.

It's not too hard to guess that "it" is the low-carb craze and desperate weight loss aspirants are getting in the Zone, going South Beach and doing it the Atkins way.

What some local doctors had to say revealed that for the overweight 60 percent of America, a high-protein diet with restricted carbohydrate consumption may have benefits as a weight loss strategy. However, there is still little to no information about the long-term health effects and how it really compares in effectiveness to the traditional low-fat diet.

"What has precipitated this interest in the low-carb diet is the role carbohydrates play in obesity development," said Jeffrey Potteiger, chairman of the department of physical education, health and sports studies at Miami University. "There is a relationship between carbohydrate intake, insulin levels and the development of diabetes."

A choice to eat "good," "complex" carbohydrates that are absorbed slowly and do not rapidly raise blood insulin levels can lead to greater overall health and less risk of diabetes and obesity, Potteiger said.

Evidence for this argument lies in the fact that a rising number of children who now commonly consume readily absorbed, "simple" carbohydrates in a high-sugar diet develop Type II diabetes, which is insulin resistance, Potteiger said.

When sugar level rises in the blood, the production of insulin is stimulated and the sugar or broken down "simple" carbohydrates are stored into fat cells for future use. The blood-sugar level drops, hunger pangs are sparked and then some are drawn to binge eating. A strictly followed low-carb diet seeks to end the insulin roller coaster.

With a low-carb diet, "You never have hunger pangs," said Dr.

John Held, a cardiologist at Mercy Hospital Fairfield, who has had patients on the diet and is currently on a carbohydrate- and refined sugar-restricted diet. "I've had patients lose 100 pounds on this diet, have their cholesterol come down, have their blood pressure come down."

In a Duke University study in 2002 by Dr. Eric Westman and funded by the Atkins Foundation, 60 adults were put on the Atkins diet and 60 others used the low-fat approach. After six months, the Atkins dieters lost an average of 31 pounds compared with 20 pounds on the low-fat diet. The Atkins dieters had a greater increase in HDL, the good cholesterol, and a larger drop in triglycerides.

However, after 12 months, both groups gained most of their weight back and others dropped out.

"Having a diet with a higher percentage of fat doesn't mean you are going to put cholesterol in your arteries," Held said. "But, there has never been a study of a large population over a long period of time for any diet. I think there is incomplete information."

"I don't know that there is more research out (about the low-carb diet) that is better than a person that eats a well-balanced diet and reduces their overall calorie consumption," Potteiger said.

Plus, behind all the marketing, there are some downsides to the diet.

First off, it is still a diet that must be strictly followed.

"The first two weeks are tough," Held said about the extreme carbohydrate restriction at the start of the diet. "You do need to follow the diet. You can't cheat the diet."

Bread, pasta, rice and potatoes are well-known as the untouchables in the low-carb world, but also in the first two weeks of many low-carb diets, fruit, legumes, lentils and even some vegetables are off limits.

Despite popular assumption, sticking to the diet does not mean chugging loads of fat to your heart's desire or until your belt bursts. Even the Atkins-recommended recipes substitute ground beef for ground chuck and instruct to use olive oil in cooking. Plus you eat until you are sustained, not full.

You could increase your stress level in trying to stay informed to make the best choices to stay on the diet, Potteiger said.

"They have to be knowledgeable about the nutrient composition they are eating," he said. If following a diet limited to 30 percent carbohydrates, "that person would have to actively think about all their food choices throughout the day. It's very difficult to do that and do it over a long period of time."

But, one could take the optimistic approach. "The fact that you have to be knowledgeable about your diet is not a bad thing. It makes you a more informed consumer," Held said.

Marketing and new product labels could fool you into thinking you are following the diet, when you are not.

The low-carb dishes at fast-food chains like Hardee's, Donatos Pizzeria, Arby's, Burger King, and Blimpie may not really be what they seem because there are no federal standards to define "net carbs," according to the Atkins Web site. A can of Coca-Cola C2 still has 18 carbs, which is almost the Atkins daily maximum in the induction period, according to the Web site. The low-carb items at the grocery store, even Atkins-approved items, may not be worth the extra pocket-digging when reduced-calorie or sugar-free foods have been found to have about the same net carbs and calories, according to the January 2004 issue of the Wellness Letter, a health research publication of the University of California Berkley.

An unbalanced diet may have side effects.

A downside to the low-carb diet is possibly not getting enough carbohydrates to maintain a normal blood-sugar level, which can cause fatigue, Potteiger said. The Atkins diet recommends during the first two weeks taking a dietary supplement for fatty acids and dietary fiber.

Drinking lots of water to balance out the dense meat is needed to avoid constipation, Held said.

The long-term health effects have not been studied and are not known, Potteiger and Held said.

Some think gaining weight back or a fluctuating weight is "more dangerous for heart health than just being heavy," Held said.

Regardless of the rave about the low-carb diet, Potteiger said the bottom line is in the calories.

"If a person is not losing weight, then somehow, someway, they need to take in less calories or expend more energy," he said.

"There is no quick fix. If weight loss was easy to do then we wouldn't have as many obese and overweight people as we do."

Dieting and exercise have been proven to be more effective than diet alone. Scheduling a workout is a important component of weight loss and staying healthy, Potteiger said.

Candice Brooks writes for the Journal News of Hamilton, Ohio.

E-mail: cbrooks@coxohio.com Editor Notes:

c.2005 Cox News Service