Milk and dairy consumption, diabetes and the metabolic syndrome: the Caerphilly prospective study

Objectives: To report a negative association between milk or dairy consumption and the metabolic syndrome and to examine associations within the Caerphilly cohort. Setting: A representative sample of men aged 45 - 59 years in Caerphilly, UK. Participants and data: Data on fasting blood glucose and plasma insulin, fasting plasma triglycerides and high- density lipoprotein cholesterol, body mass index, and blood pressure were used to define the metabolic syndrome in terms of levels of two or more variates within the top 10%. The clinical importance of the syndrome was assessed from 20- year incidence of diabetes, vascular events and deaths. The relationships between the syndrome and the consumption of milk and dairy products was examined using data from both a semiquantitative food frequence questionnaire, and from a 7- day weighed intake record which had been kept by a 1: 3 subsample of the men. Main results: There were 2375 men without diabetes in the cohort. The prevalence of the metabolic syndrome was 15%. Men with the syndrome had significantly increased risks of a subsequent ischaemic heart disease event, death or diabetes. Negative relationships were shown between both the consumption of milk and dairy produce, and the syndrome. Adjusted odds ratio in men who regularly drank a pint of milk or more daily was 0.38 (0.18 to 0.78) and that for dairy food consumption was 0.44 (0.21 to 0.91). Milk intake showed no significant trend with incident diabetes. Conclusions: The consumption of milk and dairy products is associated with a markedly reduced prevalence of the metabolic syndrome, and these items therefore fit well into a healthy eating pattern.