Dairy may protect against metabolic syndrome

Peter Elwood and co-workers from Cardiff University studied the diet and incidence of metabolic syndrome among 2375 men, and found that men who drank milk and ate dairy products regularly were 62 per cent less likely to have the syndrome. "The prevalence of the syndrome is markedly associated with the consumption of milk, and this is apparent both in men grouped by their own estimates of milk consumption, and in those grouped by milk intake data obtained from the 7-day weighed intake records,"​ wrote Elwood in the Journal of Epidemiology and Community Health​, Metabolic syndrome (MetS) is a condition characterised by central obesity, hypertension, and disturbed glucose and insulin metabolism. The syndrome has been linked to increased risks of both type-2 diabetes and CVD. Fifteen per cent of adult Europeans are estimated to be affected by MetS, while the US statistic is estimated to be a whopping 32 per cent. The Caerphilly Prospective Study assessed dietary intakes of the men (age range 45-59) using a semi-quantitative food frequency questionnaire at baseline, while a sub-sample of 603 men kept a seven-day weighed dietary intake record. The subjects had two or more markers for MetS, from high blood glucose, insulin, blood fats, body fat, and blood pressure. After 20 years of follow-up the researchers calculated that the 15 per cent of men with MetS at the start of the study were at almost double the risk of coronary artery heart disease and four times the risk of diabetes of those without the syndrome. But those who regularly drank milk and ate dairy products, such as yogurt and cheese, were significantly less likely to have the syndrome. Indeed, Elwood and co-workers report that a daily pint of milk was associated with a 62 per cent risk reduction, while regularly intake of other dairy produce reduced the risk by 56 per cent. The authors do not discus the possible mechanisms behind the apparent benefits, nor speculate on the potential constituents that may have anti-diabetic or heart healthy effects. Previously, researchers have proposed conjugated linoleic acids CLA, found predominantly in dairy products such as milk and cheese may improve insulin action and reduce blood glucose levels. Additionally, a study published in the July 2006 issue of the journal Diabetes Care​ (Vol. 29, pp. 1579-1584) reported that low-fat dairy was associated with reduced risk of diabetes amongst women. When the researchers from Harvard adjusted for vitamin D, calcium, magnesium, fat and fibre content of the diary products, the association between dairy intake and diabetes risk was still present. This suggests a potential role for other nutrients in the milk, possibly milk proteins, they stated in Diabetes Care​. Milk consumption has plummeted in the UK over the past 25 years, amid concerns about its impact on health, say the authors. But dairy produce is part of a healthy diet and its consumption should be promoted, they conclude Source: Journal of Epidemiology and Community Health​ Volume 61, Pages 695-698 "Milk and dairy consumption, diabetes and the metabolic syndrome: the Caerphilly prospective study" ​Auhors: P.C. Elwood, J.E. Pickering, A.M. Fehily