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.

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.