Should you go low fat or low carb? If you’re like most dieters, you’ve watched the trends swing back and forth a few times, and you might even have tried both programs, using trial and error to decide which is best. You don’t have to be a diet guinea pig any more. Researchers at Stanford University, led by Dr. Christopher Gardner, conducted a year-long study comparing the effectiveness and safety of a variety of low-carb and low-fat weight loss diets: Atkins, the Zone, Ornish, and LEARN.
In an article published recently in the Journal of the American Medical Association, Gardner and his research team report that participants lost weight on both low-carb and low-fat diets, but the low-carb Atkins plan produced significantly more weight loss.
Popular low-carbohydrate diets like Atkins have for some time presented a challenge to the traditional weight loss advice based on U.S. national dietary weight loss guidelines, which emphasize diets low in fat and higher in carbs. Until recently, little research addressed the question directly.
The Four Diets Compared
• The Atkins diet, lowest in carbs of the four diets studied, aims for 20 grams of carbs daily in the first 2-3 months, and then 50 grams or less thereafter. Atkins doesn’t require counting calories.
• The Zone diet emphasizes a distribution of calories that is 40% carbs, 30% protein, and 30% fat, and does require conforming to an upper limit on calories.
• The LEARN program, based on the national weight loss guidelines, recommends 55% to 60% of calories should come from carbohydrates and less than 10% from fat and includes calorie restrictions.
• The Ornish diet emphasizes low fat, with less than 10% of calories from fat.
The Study and Results: Good News for Low-Carb
A group of over 300 overweight but otherwise healthy women between 25 and 50 years old were randomly assigned to one of the four diets. The participants were given weekly instruction with a dietitian for the first two months and then continued to follow their assigned diets for ten more months.
At the end of a year, the dieters who followed the low-carb Atkins plan had lost an average of 10 pounds, while the weight loss of women who followed the other three diets averaged between 3 and a little less than 6 pounds.
The researchers also checked the women’s cholesterol and other lipids and their insulin levels. More good news: they found no significant danger of elevated cholesterol as a result of following the low-carb program.
Does This Mean Everyone Should Do Atkins?
So, should you go low-carb? The Stanford study suggests it might be a good idea, especially if you’re otherwise healthy and have had disappointing results with traditional low-fat, high-carb approaches. Because this study did not include women who had been diagnosed with high blood pressure or diabetes, if you have either of those conditions, you should probably check with your physician before beginning a low-carb diet.