For men who want to quickly lose weight, it’s better to cut carbohydrates than to cut fat, a small study suggests.
When overweight men who were otherwise healthy followed either a low-fat or low-carbohydrate diet for 50 days, they tended to lose more weight and body fat, particularly in the trunk area, when they stuck with the low-carb regimen.
Women who participated in the study also tended to lose more weight by cutting back on carbs, but the difference between the low-carb diet and the low-fat regimen was less dramatic.
Although the study was relatively short, previous research shows the low-carb diet may surpass the low-fat diet even after up to one year of dieting, study author Dr. Jeff S. Volek told AMN Health.
“I certainly stand behind our research, which has shown that these diets are effective,” the researcher, based at the University of Connecticut in Storrs, told Reuters Health.
The current study was funded by the Dr. Robert C. Atkins Foundation. Dr. Atkins was the creator of the low-carbohydrate Atkins diet.
In an interview, Volek said that previous investigations of low-carb diets have measured overall weight loss, and not where people tend to lose that weight, or body fat. This is an important consideration, he and his colleagues argue in the journal Nutrition & Metabolism, given that extra abdominal fat is linked to diabetes, atherosclerosis and other health problems.
To investigate, Volek and his team asked 15 overweight men to follow either a low-fat or a low-carb diet, for 50 days. Thirteen overweight women did the same for 30 days, to control for the effects of their menstrual cycle. Each participant then switched to the other diet.
While following the low-fat regimen, participants ate mostly whole grains, fruits, vegetables and low-fat dairy and meats. Approximately 55 percent of calories were carbohydrates, and 25 percent stemmed from fats.
During the low-carb diet, participants cut their intake of carbohydrates to 10 percent of total calories, while fats made up 60 percent of daily intake. Low-carb staples included beef, poultry, oils, nuts, eggs, and some vegetables.
The researchers found that the majority of men lost more weight, fat and trunk fat on the low-carb diet than while following the low-fat regimen. Five men lost at least 10 pounds more after cutting carbs than fat.
Women also appeared to shed more pounds and fat following the low-carb diet, but to a lesser extent than men.
Experts have questioned whether the low-carb diet - which allows people to eat high-fat fare - is safe over the long term, and it remains unclear how the diet affects the heart and blood vessels, as well as kidney and bone health.
In response, Volek noted that previous research has shown that low-carb dieters experience a bigger decrease in cholesterol than when they opt for low-fat fare.
“I think we’re going to see many changes” in how people think about dieting, he said. “But there are still many people who cling to the fact that the low-fat diets are the way to go.”
SOURCE: Nutrition & Metabolism, November 2004.
Revision date: June 11, 2011
Last revised: by Janet A. Staessen, MD, PhD