Long-term association between dairy consumption and risk of childhood obesity: a systematic review and meta-analysis of prospective cohort studies

Abstract

Background/objectives: Data from small-scale, short-term, clinical trials suggest a beneficial effect of dairy consumption on the risk of childhood obesity; however, the long-term association is unclear. Therefore, we aim to examine the longitudinal association between dairy consumption and the risk of overweight/obesity in children and adolescents by conducting a systematic review and meta-analysis of prospective cohort studies.

Subjects/methods: Eligible studies were identified by searching PubMed and EMBASE through March 2015. Additional studies were retrieved via Google Scholar or a hand review of the reference lists from relevant articles. Pooled associations of interest were estimated by using a random-effects model. The heterogeneity for each pooled analysis was evaluated by I(2) statistic as well as by Cochran's Q test. Publication bias was assessed by using both Egger's and Begg's tests.

Results: Ten studies comprising 46,011 children and adolescents with an average 3-year follow-up were included. As compared with those who were in the lowest group of dairy consumption, children in the highest intake group were 38% less likely to have childhood overweight/obesity (pooled odds ratio (OR)=0.62; 95% confidence interval (CI): 0.49, 0.80). With each 1 serving/day increment in dairy consumption, the percentage of body fat was reduced by 0.65% (β=0.65; 95% CI: -1.35, 0.06; P=0.07), and the risk of overweight/obesity was 13% lower (OR=0.87; 95% CI: 0.74, 0.98).

Conclusions: Accumulated evidence from prospective cohort studies suggests that dairy consumption is inversely and longitudinally associated with the risk of childhood overweight/obesity. Further studies are warranted to examine the types of dairy products in relation to the risk of childhood overweight/obesity.