Obese women encouraged to eat water-rich foods lost significantly more weight than counterparts who were told to eat less fat. The women in the first group were in a program based on reducing the energy density of what they ate. By the six-month mark they had lost 9.4 kg. The control group also lost weight — but not as much: 6.7 kg at that point.
"Incorporating low-energy-dense foods into a diet was more effective for weight loss than reducing fat alone," said investigator Julia Ello-Martin, a doctoral candidate from Pennsylvania State University in University Park. The 12-month trial enrolled 101 obese women in their mid-40s with body mass index (BMI) scores between 30 and 40 kg/m2. All participants received individual counseling, but neither the energy-density cohort nor the reduced-fat cohort was given a specific regimen to follow.
Instead, the experiment plied the energy-density group with positive messages, according to Ms. Ello-Martin. The women were encouraged to eat fruits, vegetables, legumes, whole grains, soups, and high-fiber and reduced-fat foods. Portion size was not an issue.
In contrast, the reduced-fat group was counseled to limit portions and eat less fat. Although this cohort also lost weight, Ms. Ello-Martin said the energy-density group pulled ahead by the fourth month.
After the first six-month period, the women in the ED group had lost 21 pounds while the women in the RF group had lost only 15 pounds. The women in the ED group also significantly lowered the energy density of their diet versus the RF group but there was no difference in fat intake.
This is the first long-term study to look at how a low energy density diet can affect body weight. It’s important because it shows that a healthy diet pattern can result in significant weight loss without counting calories or fat grams.
One argument for the energy-density approach is that dieters can eat larger portions without increasing calories. "Women in the energy-density group were able to consume a significantly greater amount of food than women in the reduced fat group," Ms. Ello-Martin said. Consequently, she suggested they were less likely to feel hungry.
Session chair Holly Wyatt, MD, from the University of Colorado in Denver, said the energy-density diet is another approach to getting people to consume fewer calories. Some people may be more successful because they can eat a larger volume of food for the same amount of calories, she said.
NAASO 2004 Annual Scientific Meeting: Abstract 90-OR. Presented Nov. 17, 2004.