Last week's bankruptcy filing by Atkins Nutritionals is seen by many as the end of the public's appetite for a low-carbohydrate diet that encouraged virtually unlimited consumption of porterhouse steak, butter and pork rinds.
Nutrition experts see this as the proper outcome for a diet that was often at odds with the large body of nutritional research showing the benefits of eating a diet rich in fruit and vegetables, whole grains, lean protein and moderate or low in healthy fat. But many also see value in what Atkins did, even if they think his methods were flawed and his approach was unhealthy.
"The good that Atkins did is that he made people more mindful about the importance of limiting refined carbohydrates like sugar and white flour," said cardiologist Dean Ornish, a proponent of a very-low-fat, high-carbohydrate approach to lose weight and lower the risk of heart disease. "The bad is that he taught people that in the short run, you can sell a lot of books and make a lot of money telling them what they want to hear."
But Atkins also "taught the scientific community a good lesson," said Gary Foster, clinical director of the Weight and Eating Disorders Program at the University of Pennsylvania. "Don't be so quick to judge new approaches."
The best-selling success of Atkins diet books was a cultural phenomenon that researchers couldn't ignore. "We can't test every fad diet," Foster said. "So why did we test this one? Because 10 million people had bought the book."
In studying the very-low-carbohydrate, high-protein, high-saturated-fat approach that Atkins promoted for quick weight loss, researchers found some surprises. "It's clear that the Atkins diet does better in the short term and doesn't do any worse in the long run in terms of weight control," said Walter Willett, professor of nutrition at the Harvard School of Public Health. "That was so contrary to the general nutritional dogma that it really did shake things up a bit, which is good."
Also unexpected was that a rigorous, independent study of people on the Atkins approach revealed the opposite of what many doctors had feared: Participants' blood fat levels either were the same as or slightly better than those of people who followed a conventional low-fat weight regimen for a year. "Who would have predicted that?" said Foster, author of the study, which was published in the New England Journal of Medicine. "Certainly, it wouldn't have been me."
But experts say that it's still not known what the long-term health effects are of limiting fruit, vegetables, whole grains, fiber and dairy products such as milk, yogurt and cheese. Those questions may be answered by a two-year, federally funded study of 300 people on a very-low-carbohydrate diet that is being led by Foster. The study is examining the diet's effect on blood vessels, muscle, bone and a variety of other measures. "Whether anyone will care about the results, I don't know," Foster said. "But we're going to continue."
Here's what else leading nutrition experts said the Atkins experience has shown:
Quick weight loss doesn't last. By severely restricting carbohydrates, the body is depleted of glycogen, a substance that helps retain water. The quick weight loss on Atkins is initially due to loss of water, not fat. "The downside is that rapid weight loss, whether with this diet or another one, doesn't last long-term," said American Heart Association president Robert Eckel, professor of medicine at the University of Colorado Health Sciences in Denver.
Protein is important. Studies have long shown that protein increases satiety -- feeling full. When University of Cincinnati School of Nursing researchers put overweight women on an Atkins diet, their hunger decreased. Initially, they lost weight faster than women on a conventional low-fat diet, but by six months there was no statistical difference between the two groups. Women on the Atkins diet, "had protein with breakfast, protein with lunch and protein with dinner," said Bonnie Brehm, lead author of the study. "I was amazed at how satisfied they were, and they didn't crave snacks."
Taste counts. The Atkins diet launched numerous new lines of low-carbohydrate products from many food manufacturers that flooded grocery stores. "Two years ago, they filled half a grocery wall, now they're just a stand-alone unit because they didn't taste very good and they were expensive," Brehm said.
Diets don't work. It takes consistent lifestyle changes to lose weight and maintain it. "Americans tried [Atkins]," Brehm said. "It worked for a while and then it didn't continue to work, so they abandoned it. . . . The message is moderation, moderation, moderation. But people don't really want to hear that. It's not sexy."
Too many processed, sugary carbohydrates are unhealthy. "Atkins was good in pointing out that refined grains can be a problem, but bad in making any carbohydrate out to be a toxin," said Michael Jacobson, executive director of the Center for Science in the Public Interest. Consumption of sugary soft drinks, he said, "has declined by about 12 percent over the last six years. That's an historic turnaround, and I suspect that Atkins, South Beach and Sugar Busters had something to do with it."
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