No effects of low and high consumption of dairy products and calcium supplements on body composition and serum lipids in Puerto Rican obese adults

Abstract

Objective: Epidemiologic studies have shown that a high calcium intake is related to lower body weight, fat, and serum lipids in obese individuals. However, clinical studies have shown inconclusive results. The present study was conducted to determine if dairy or calcium supplementation alters body composition or serum lipids in Puerto Rican obese adults without dietary energy restriction or exercise.

Methods: A 21-wk randomized clinical trial was conducted in 30 obese adults, aged 21-50 y, with usual calcium intakes <700 mg/d. Subjects were randomly assigned to the following: high dairy (∼ 1300 mg/d of calcium from dairy products by substituting foods); high calcium (∼ 1300 mg/d of calcium; ∼ 700 mg/d from diet and 600 mg/d from a supplement); or placebo. Subjects were asked to continue their established dietary intake (except for the high dairy group) and their physical activity during the study. Body weight was measured monthly; body fat, bone, and serum lipids (total cholesterol, high-density lipoprotein, low-density lipoprotein, and triacylglycerol) were measured at baseline and at 21 wk. Pairwise differences in study endpoints among the groups were assessed using ANOVA and post-hoc analysis.

Results: Grand mean calcium intake was 1200 ± 370 (median 1187) mg/d in the high dairy group, 1171 ± 265 (median 1165) mg/d in the high calcium group, and 668 ± 273 (median 691) mg/d in the control group, which was significantly lower compared to the two treatment groups (P < 0.001). There were no significant group effects in any of the outcome variables.

Conclusion: A high dairy or calcium diet alone did not alter body composition or serum lipids profile in a sample of Puerto Rican obese adults.

Fig. 1

Calcium intake estimated from food records and FFQ during the study. Repeated measures ANOVA and post-hoc multiple pairwise by Bonferroni showed a significant increased in calcium intake from baseline to month 2 and then on in the high dairy group and high elemental group (P < 0.001). There was no increase in calcium intake at any point during the study in the control group (P = 0.38). ^*Significantly different from the control group (P < 0.05).

Fig. 2

Energy intake estimated from food records during the study. No significant difference was observed between groups throughout the study by repeated measures ANOVA and post-hoc multiple pairwise by Bonferroni (P = 0.806).

Fig. 3

Physical activity index during the study. No significant difference was observed between groups throughout the study by repeated measures ANOVA and post-hoc multiple pairwise by Bonferroni (P = 0.764).