Portland, OR — Something as simple as keeping a food diary can double a person's weight loss, according to recent research.

“The more food records people kept, the more weight they lost,” says lead author Jack Hollis, a researcher at Kaiser Permanente's Center for Health Research in Portland, OR. “Those who kept daily food records lost twice as much weight as those who kept no records. It seems that the simple act of writing down what you eat encourages people to consume fewer calories.”

In addition to keeping food diaries and turning them in at weekly support group meetings, participants were asked to follow a diet rich in fruits and vegetables and low-fat or non-fat dairy, attend weekly group sessions, and exercise at moderate intensity levels for at least 30 minutes a day. After six months, the average weight loss among the nearly 1,700 participants was approximately 13 pounds. More than two-thirds of the participants (69 percent) lost at least nine pounds, enough to reduce their health risks and qualify for the second phase of the study, which lasted 30 months and tested strategies for maintaining the weight loss.

This is one of the few studies to recruit a large percentage of African-Americans as study participants (44 percent). African-Americans have a higher risk of conditions that are aggravated by being overweight, including diabetes and heart disease. In this study, the majority of African-American participants lost at least nine pounds, which is higher than in previous studies.

Researchers note that even small weight loss can offer health benefits. For example, a five-pound weight loss was recently shown to reduce the risk of developing high blood pressure by 20 percent.

The findings were published in the August issue of the American Journal of Preventive Medicine and funded by the National Heart, Lung and Blood Institute at the National Institutes of Health.