Intake of milk with added micronutrients increases the effectiveness of an energy-restricted diet to reduce body weight: a randomized controlled clinical trial in Mexican women

Abstract

Background: Micronutrient deficiencies have been associated with an increase in fat deposition and body weight; thus, adding them to low-fat milk may facilitate weight loss when accompanied by an energy-restricted diet.

Objective: The objective was to evaluate the effect of the intake of low-fat milk and low-fat milk with added micronutrients on anthropometrics, body composition, blood glucose levels, lipids profile, C-reactive protein, and blood pressure of women following an energy-restricted diet.

Design: A 16-week randomized, controlled intervention study.

Participants/settings: One hundred thirty-nine obese women (aged 34±6 years) from five rural communities in Querétaro, Mexico.

Intervention: Women followed an energy-restricted diet (-500 kcal) and received in addition one of the following treatments: 250 mL of low-fat milk (LFM) three times/day, 250 mL of low-fat milk with micronutrients (LFM+M) three times/day, or a no milk control group (CON). Weight, height, and hip and waist circumferences were measured at baseline and every 4 weeks. Body composition measured by dual-energy x-ray absorptiometry, blood pressure, and blood analysis were done at baseline and at the end of the 16 weeks.

Main outcome measures: Changes in weight and body composition.

Statistical analysis: One-factor analysis of variance, adjusted by age, baseline values, and community random effects.

Results: After the 16-week intervention, participants in the LFM+M group lost significantly more weight (-5.1 kg; 95% CI: -6.2 to -4.1) compared with LFM (-3.6 kg; 95% CI: -4.7 to -2.6) and CON (-3.2 kg; 95% CI: -4.3 to -2.2) group members (P=0.035). Body mass index change in the LFM+M group (-2.3; 95% CI: -2.7 to -1.8) was significantly greater than LFM group members (-1.5; 95% CI: -2.0 to -1.1) and CON group members (-1.4; 95% CI: -1.9 to -0.9) (P=0.022). Change in percent body fat among LFM+M group members (-2.7%; 95% CI: -3.2 to -2.1) was significantly higher than LFM group members (-1.8%; 95% CI: -2.3 to -1.3) and CON group members (-1.6%; 95% CI: -2.2 to -1.0) (P=0.019). Change in bone mineral content was significantly higher in LFM group members (29 mg; 95% CI: 15 to 44) and LFM+M group members (27 mg; 95% CI: 13 to 41) compared with CON group members (-2 mg; 95% CI: -17 to -14) (P=0.007). No differences were found between groups in glucose level, blood lipid profile, C-reactive protein level, or blood pressure.

Conclusions: Intake of LFM+M increases the effectiveness of an energy-restricted diet to treat obesity, but had no effect on blood lipid levels, glucose levels, C-reactive protein, or blood pressure.