Dairy consumption and metabolic syndrome: a systematic review of findings and methodological issues

A growing body of observational research suggests that dairy consumption may have a beneficial effect on the metabolic syndrome (MetS). MetS is a clustering of cardiometabolic risk factors within an individual that carries with it an increased risk of developing cardiovascular disease. A systematic search of electronic databases identified cross-sectional studies (n = 10) and prospective cohort studies (n = 3) that assessed dairy intake in relation to MetS. The quality of the included studies was assessed based on study methodology, measurement and reporting of dietary intake, use of standardized MetS diagnostic criteria and statistical analysis. Dairy intake was inversely associated with incidence or prevalence of MetS in seven out of 13 studies. Three studies found no association between dairy and MetS. Three studies reported mixed relationships between specific dairy foods and MetS. The majority of studies suggested a potential benefit of dairy consumption on the risk of having MetS, but methodological differences, potential biases and other limitations in the studies conducted prevent conclusions to be drawn. Future randomized controlled trials are needed to confirm the effect of dairy consumption on MetS.