If you're trying to lose weight by dieting, there are three main ways to go about it: cut calories, cut fat or cut carbohydrates. Critics are fighting bitterly over which works best, and whether the low-carb approach is safe and effective. Medical researchers are just now weighing in with the first scientific findings on cutting carbs. So are these new studies red meat for Atkins followers, or for Atkins critics?
For millions of Americans trying to lose weight, the Atkins diet has been a revelation. Yet, most of what we know about it comes from anecdotes.
Roseanne Clampet lost 90 pounds on Atkins in less than two years. Her story might seem hard to believe, but not to Nora Carter, a hair dresser profiled by NBC affiliate WPMI-TV in Mobile, Ala. She started on an Atkins diet in 2000 and lost 60 pounds. She says she has kept it off for three years. John Callahan of Elmira, N.Y., told WETM-TV he quickly lost 50 pounds on Atkins.
As the Atkins success stories have spread, so have its legion of devotees. Rick Burns was a participant in Dateline's recent “Diet Challenge” series. In 10 months, on the Atkins low-carb diet, Rick lost 108 pounds.
But there are other Atkins stories we heard, like the one from Rebecca Solom, interviewed by NBC affiliate KSDK in St. Louis. Rebecca lost weight on Atkins, but says she experienced some dizziness as a side effect as well.
And Marsha Davis told NBC station KFOR TV in Oklahoma City that Atkins made her have heart palpitations. She quit the low-carb diet after three days.
So how safe is the Atkins diet? Because of the rising popularity of the diet, and the criticism leveled at it by nutritionists, the medical community has begun to take a closer look, with the first scientific studies.
Dr. Linda Stern is an internist at the Veterans Hospital in Philadelphia and an assistant professor of medicine at the University of Pennsylvania. She co-authored one of the first published research studies on the impact of a low-carb diet on weight loss and health.
In 2002 Dr. Stern and her colleagues monitored more then 100 volunteers for six months. Half were placed on a conventional low-fat diet, the other half was placed on a low-carb diet -- meaning almost no bread, pasta or sugar.
Dr. Stern: “After six months, the low-carbohydrate group lost significantly more weight then the group following the low fat diet.”
Her study was published May 2003 in The New England Journal of Medicine.
Robert Bazell: “So, in this one experiment, the Atkins diet-- style diet did better?”
Dr. Stern: “It did, in terms of weight loss and also in some other important parameters.”
The “other parameters,” as she calls them, are among the most surprising discoveries of her research. After six months, although those on the low-carb diet were not restricted in the amount of saturated fats they could consume, they did not show any increase in bad cholesterol. In fact they showed an increase in good cholesterol. And members of the low-carb test group showed another benefit: a decrease in the level of triglycerides, a measure of fat in the blood that can also lead to heart disease.
Bazell: “Because everybody worries that an Atkins style diet is going to put people an increased risk for heart disease. That's the big criticism.”
Dr. Stern: “Correct.”
Bazell: ”And your results didn't show that?”
Dr. Stern: “No. It didn't.”
Other scientific studies, published in the last two years, have offered similar findings. Researchers at the University of Cincinnati and the University of Pennsylvania found that volunteers who followed a low-carb diet over the course of six months lost more weight compared to those on a more traditional low fat diet and showed significant decreases in total cholesterol.
Perhaps you are thinking this is great news, that the Atkins low-carb approach is the best of both worlds, weight loss and important health benefits. But not so fast say the experts.
Dr. Stern: “At this point, it’s yes. [But] the answer is we don't know the long term effects of Atkins.”
Bazell: “So, the scientific evidence about the effectiveness of a low-carb diet only goes out to six months right now.”
Dr. Stern: “That's correct.”
In fact one study showed that after 12 months, the difference in weight loss between Atkins and a traditional low-fat diet was not significant. So what are we to make of the Atkins diet?
Dr. Stern: “For the short term, it certainly appears to be an effective way to lose weight and a safe way to lose weight. However, without the long-term evidence, we certainly cannot give the conclusive answer.”
So when might we get a more comprehensive picture about low-carb living and it's long term effects? The Federal government is sponsoring a study right now at the University of Pennsylvania. it should be completed within three years. Until then, health professionals say the most effective way to lose weight and keep it off is to watch calories and exercise.