Effect of a dairy- and calcium-rich diet on weight loss and appetite during energy restriction in overweight and obese adults: a randomized trial

Abstract

Background/objectives: A diet rich in dairy and calcium (Ca) has been variably associated with improvements in body composition and decreased risk of type 2 diabetes. Our objective was to determine if a dietary pattern high in dairy and Ca improves weight loss and subjective appetite to a greater extent than a low dairy/Ca diet during energy restriction in overweight and obese adults with metabolic syndrome.

Subjects/methods: A total of 49 participants were randomized to one of two treatment groups: Control (low dairy, ≈ 700 mg/day Ca, -500 kcal/day) or Dairy/Ca (high dairy, ≈ 1400 mg/day Ca, -500 kcal/day) for 12 weeks. Body composition, subjective ratings of appetite, food intake, plasma satiety hormones, glycemic response and inflammatory cytokines were measured.

Results: Control (-2.2 ± 0.5 kg) and Dairy/Ca (-3.3 ± 0.6 kg) had similar weight loss. Based on self-reported energy intake, the percentage of expected weight loss achieved was higher with Dairy/Ca (82.1 ± 19.4%) than Control (32.2 ± 7.7%; P=0.03). Subjects in the Dairy/Ca group reported feeling more satisfied (P=0.01) and had lower dietary fat intake (P=0.02) over 12 weeks compared with Control. Compared with Control, Dairy/Ca had higher plasma levels of peptide tyrosine tyrosine (PYY, P=0.01) during the meal tolerance test at week 12. Monocyte chemoattractant protein-1 was reduced at 30 min with Dairy/Ca compared with Control (P=0.04).

Conclusions: In conclusion, a dairy- and Ca-rich diet was not associated with greater weight loss than control. Modest increases in plasma PYY concentrations with increased dairy/Ca intake, however, may contribute to enhanced sensations of satisfaction and reduced dietary fat intake during energy restriction.

Figure 1

Delta total area under the curve (A) and change from baseline values for plasma PYY (B) during a 4 h meal tolerance test in participants consuming control or dairy/Ca at wk 0 and wk 12. Values are means ± SE, n=18 (control) and n=20 (dairy/Ca). ○ Control, □ Dairy/Ca * Different from control at indicated time point, P<0.05.

Figure 2

Weekly subjective rating of satisfaction (A) and regression analysis (B) showing the relationship between delta energy intake from wk 0 to wk 12 (kcal) and Ca (mg) intake. In Panel A, values are means ± SE, n=18 (control) and n=20 (dairy/Ca). ○ Control, □ Dairy/Ca. * Different from control at indicated time point, P < 0.05. In Panel B, the regression is represented by R=0.40, r² =0.16, df=28, P = 0.027.