Elizabeth S. Reames | 4/19/2005 10:28:33 PM
Eating a diet high in fruits, vegetables, reduced-fat dairy products and whole grains may help control weight, according to LSU Agricultural Center nutritionist Dr. Beth Reames.
A recent study found that participants eating more of these foods had smaller gains both in Body Mass Index (BMI) and waist circumference than those eating less of these foods.
Reames says that higher-fiber foods are more nutrient dense and may help to satisfy appetite and thus prevent weight gain.
Scientists funded by the Agricultural Research Service studied volunteers' everyday eating habits to better understand dietary causes of obesity.
Reames says obesity has increased by more than 20 percent in the past decade in the United States. About 60 percent of U.S. adults are now overweight or obese.
The scientists looked at the food-consumption habits of 459 healthy men and women participating in the ongoing Baltimore Longitudinal Study on Aging. Five dietary patterns were determined from seven-day dietary records. These dietary patterns were labeled "healthy," "white bread," "alcohol," "sweets" and "meat and potatoes." The names reflect the foods that contributed relatively greater proportions of caloric intake in each pattern.
Subjects eating the "healthy" pattern had the highest intake of foods such as high-fiber cereal, reduced-fat dairy, fruit, nonwhite bread, whole grains, beans and legumes and vegetables and the smallest gains in BMI and waist circumference.
The "healthy" pattern group ate a significantly higher percentage of calories from carbohydrate, about 62 percent, than the other groups. The healthy dietary pattern was similar to the Dietary Approaches to Stop Hypertension (DASH) diet, which has been shown to decrease blood pressure.
Compared to the "healthy" pattern groups, all of the other groups had higher increases in BMI and waist circumference. Those in the "healthy" cluster gained an average 1/6-inch in waist circumference per year, while those in the "white bread," "alcohol" and "meat and potatoes" clusters gained close to a half-inch per year. Researchers said that those in the "meat and potatoes" group gained in both waist circumference and BMI, and those in the "white bread" group—and to a lesser extent, the "alcohol" group—disproportionately gained waist circumference relative to BMI.
Reames explains that body mass index is currently used to determine weight status. Overweight is defined as a BMI of 25 to 29.9, and a BMI of 30 and above defines obesity.
Although BMI is a common measure used to indicate body fat, waist circumference is used to indicate abdominal fat. The LSU AgCenter nutritionist points out that excess fat in the abdomen, independent of total body fat, is considered a risk factor for heart disease and type 2 diabetes.
Abdominal obesity is considered a risk factor when waist circumference exceeds 40 inches for men or 35 inches for women. Because gains in waist circumference are particularly related to greater health risks, Reames says it's important to monitor changes in waist circumference as well as total weight gain, and to try to minimize abdominal weight gain.
For information about eating more fruits, vegetables, whole-grains, low-fat dairy and lean meat choices, contact an LSU AgCenter Extension agent in your area. For information on related family and consumer topics, visit the FCS Web site at http://www.lsuagcenter.com/Inst/