More Carbs, More Exercise = More Weight Loss
Studies Link High-Fiber Carbs, Low Weight
March 5, 2004 -- The thinnest people eat the most carbs, a four-nation survey shows.
If you've been following the latest U.S. diet fads, that isn't what you'd expect. But the data come from an intensive, four-nation study of more than 4,000 men and women age 40 to 59. The study was based on food diaries kept by people in the U.S., U.K., Japan, and China.
Study leader Linda Van Horn, PhD, of Northwestern University, presented the findings at the 44th American Heart Association Annual Conference on Cardiovascular Disease Epidemiology and Prevention, held this week in San Francisco.
"Without exception, a high-complex-carbohydrate, high-vegetable-protein diet is associated with low body mass," Van Horn said in a news conference. "High-protein diets were associated with higher body weight."
Don't be misled. The high-carb diet that's keeping the pounds off is full of high-fiber vegetables, not french fries.
"The point we are trying to make is that what we consider desirable carbohydrates are complex, or high-fiber-containing carbohydrates: whole grains, fruits, and vegetables -- not doughnuts or even polished rice," Van Horn said. "We are looking at legumes and vegetables that offer fiber as well as protein. We're not talking about refined carbohydrates, commonly known as sugar."
Not surprisingly, people who exercised more also tended to be less heavy. This was true even though they tended to consume more calories.
What Are Americans Eating?
In another conference presentation, Mayo Clinic researcher Randal J. Thomas, MD, reported the results of a study of what people in Olmstead County, Minn., are eating. The researchers polled 1,200 county residents every year from 1999 to 2003.
From 1999 to 2000, they found, people's diets got better in terms of eating fewer high-fat foods and in daily cholesterol intake. But in 2001 and 2002, reported diets got worse and worse.
The culprit? Thomas suspects it was the low-carb, high-fat diets that became increasingly popular in that time period.
"We don't have specific data, but until 2001 there was a trend to improve, then a trend upward for fats and cholesterol. This correlates with popularity of these plans," Thomas said in a news conference. "It is pretty clear from marketing data that over the past two years there have been significant trends toward more fat intake in the diet. If that is true, there are rough times ahead in terms of disease risk."
Thomas refused to name any specific diet plan. He said that decreasing calories and cutting back on simple carbohydrates is a great idea. But any plan that increases the amount of saturated fat in one's diet is "a problem," he said.
Is It Dinner With No Meat?
How do Americans feel about eating their veggies? Fairly guilty, suggest data reported by Stanford University researcher Alison Jane Rigby, PhD, MPH, RD.