Dietary energy density in the treatment of obesity: a year-long trial comparing 2 weight-loss diets

• Published in: The American journal of clinical nutrition 2007-06, Vol.85 (6), p.1465-1477
• Main Authors: Ello-Martin, Julia A, Roe, Liane S, Ledikwe, Jenny H, Beach, Amanda M, Rolls, Barbara J
• Format: Article
• Language: English
• Subjects: Adult; adults; Biological and medical sciences; diet therapy; Diet, Reducing; dietary fat; Dietary Fats - administration & dosage; energy density; Energy Intake; Exercise; Feeding. Feeding behavior; Female; food choices; Fruit; fruits (food); Fundamental and applied biological sciences. Psychology; Humans; Hunger; low calorie diet; low fat diet; Middle Aged; obesity; Obesity - diet therapy; Obesity - physiopathology; Patient Satisfaction; satiety; Vegetables; Vertebrates: anatomy and physiology, studies on body, several organs or systems; weight control programs; Weight Loss; women
• ISSN: 0002-9165; 1938-3207
• DOI: 10.1093/ajcn/85.6.1465

BACKGROUND: Consuming foods low in energy density (kcal/g) decreases energy intake over several days, but the effectiveness of this strategy for weight loss has not been tested. OBJECTIVE: The effects on weight loss of 2 strategies for reducing the energy density of the diet were compared over 1 y. DESIGN: Obese women (n = 97) were randomly assigned to groups counseled either to reduce their fat intake (RF group) or to reduce their fat intake and increase their intake of water-rich foods, particularly fruit and vegetables (RF+FV group). No goals for energy or fat intake were assigned; the subjects were instructed to eat ad libitum amounts of food while following the principles of their diet. RESULTS: After 1 y, study completers (n = 71) in both groups had significant decreases in body weight (P < 0.0001). Subjects in the RF+FV group, however, had a significantly different pattern of weight loss (P = 0.002) than did subjects in the RF group. After 1 y, the RF+FV group lost 7.9 ± 0.9 kg and the RF group lost 6.4 ± 0.9 kg. Analysis of all randomly assigned subjects also showed a different pattern of weight loss between groups (P = 0.021). Diet records indicated that both groups had similar reductions in fat intake. The RF+FV group, however, had a lower dietary energy density than did the RF group (P = 0.019) as the result of consuming a greater weight of food (P = 0.025), especially fruit and vegetables (P = 0.037). The RF+FV group also reported less hunger (P = 0.003). CONCLUSION: Reducing dietary energy density, particularly by combining increased fruit and vegetable intakes with decreased fat intake, is an effective strategy for managing body weight while controlling hunger.