January 01, 2003
Atkins vs. low-fat diets
Westman's results seem to go against the grain of just about everything doctors have been telling patients for the last two decades as far as reducing heart-attack risk: eat less fat and more vegetables and complex carbohydrates.
So, what's a body to do?
Many apparently are jumping on the Atkins bandwagon.
The Atkins diet, which has been around for 30 years, recently shot up national best-seller lists, partly as a result of Westman's study and partly because of a New York Times story last summer in which some leading researchers suggested that over-emphasis on low-fat, high-carbohydrate diets could be the reason behind Americans' growing obesity problem. Those and other reports have sparked a continuing debate among physicians and nutritionists over which dietary approach is best.
Many who have used the Atkins diet swear by it.
Interviews with several physicians – including some practitioners who think high-fat diets have merit – suggest that patients who are concerned about their weight or cholesterol probably shouldn't rush to embrace high-fat diets – at least until more facts are in.
(Westman isn't endorsing Atkins yet either. Patients at Duke's Diet and Fitness Center, where Westman works, are still being prescribed a low-fat "Mediterranean" diet, not Atkins, he said.)
Above all, physicians warn, people who have read or heard about the recent diet reports should not conclude that it's OK to eat all the fat they want.
UK's Dr. James Anderson, a widely known nutritionist and champion of low-fat, high-fiber diets, remains unconvinced by the latest positive reports about Atkins.
Anderson led a study in 2000 that calculated that long-term use of the Atkins diet could produce a 30 percent increase in cholesterol and a corresponding 30 percent increase in risk for heart attack.
"Even if the Atkins diet were shown to offer better short-term weight loss, I still think it's the wrong way to go long-term," Anderson said. "Everything we know says that high fat intake increases your risk for heart disease and cancer."
However, in Westman's study, 120 overweight volunteers were randomly assigned to the Atkins Diet or the American Heart Association's low-fat Step I Diet for six months.
Total cholesterol fell slightly in both groups, but users of the Atkins diet had an 11 percent increase in HDL and a 49 percent drop in triglycerides. For those on Step I, HDL was unchanged, and triglycerides fell 22 percent.
Westman admitted he was surprised by the improvement in cholesterol among the Atkins diet users and doesn't know how the high-fat diet could have produced such a reduction.
"That's a question that urgently needs to be answered by further research," Westman said.
In addition, Westman said, his six-month study was too brief to draw any conclusions about Atkins' long-term effects on cholesterol. He noted that the National Institutes of Health is planning a one-year study of the diet that could be revealing.
"We don't think there's enough information yet to say the diet is a good thing," he said. "We do think we can say that we haven't found anything bad yet."
Bensema said he remains skeptical about findings that suggest Atkins is superior to Step I. He noted that Westman did not compare Atkins to the Heart Association's more restrictive Step II diet.
"There is no situation in which I would tell someone to go on the (Atkins) diet," Bensema said. "If someone came to me insisting on doing it, and they didn't have diabetes or renal dysfunction, I would not oppose them going on it. But I would advise them that they should be monitored closely and limit the time they're on the diet."
Defining diets
Unlike regimens designed to promote weight loss by reducing fat consumption, the Atkins diet aims to reduce weight by sharply cutting back on processed or refined carbohydrates, including foods such as bread, pasta, cereal and starchy vegetables. Eating protein, however, is encouraged.
The American Heat Association's Step I and Step II diets are aimed primarily at reducing risk for coronary heart disease. Both diets primarily seek to reduce fat and cholesterol by cutting back on foods such as fried meats and fried vegetables and encouraging more fresh fruit and vegetables.
Online
- Information about the Atkins diet is available online at
www.atkinscenter.com.
- For details about the American Heart Association Step I and Step II diets, go to
www.deliciousdecisions.org.
http://www.recordonline.com/archive/2003/01/01/bz01.htm