Introduction and Executive Summary of the Supplement, Role of Milk and Dairy Products in Health and Prevention of Noncommunicable Chronic Diseases: A Series of Systematic Reviews.

Milk and dairy products contain multiple nutrients and contribute significantly to meet the nutritional requirements for protein, calcium, magnesium, phosphorus, potassium, zinc, selenium, vitamin A, riboflavin, vitamin B-12, and pantothenic acid. However, consumption of dairy is decreasing and moving away from the advised level in many countries and the potential benefits of milk and dairy products for health have come under question. This, in spite that numerous studies report health benefits associated with dairy consumption. The present supplement aims to assess and summarize scientific evidence regarding the impact of dairy intake on health and all-cause mortality, and on the prevention of diverse chronic diseases, mainly from meta-analyses of observational studies and randomized controlled trials (RCTs). There seem to positive associations between moderate maternal milk intake during pregnancy and infant birth weight, length and bone mineral content during childhood. Moreover, consumption of dairy products in older subjects may reduce the risk of frailty and decrease the risk for sarcopenia. The highest consumption of dairy products did not show a clear association with total osteoporotic fracture and hip fracture risk; however, a diminished risk of vertebral fracture was found. Analysis of the differences between high and low dairy consumption and for dose-response found no association between dairy product consumption and risk of all-cause mortality. Total and low-fat dairy consumption is associated with a reduced risk of developing metabolic syndrome and current evidence supports that consumption of dairy does not adversely affect the risk of cardiovascular outcomes and may even have a subtle protective effect. Moreover, evidence has been provided of an inverse association between the consumption of dairy products and ischemic heart disease and myocardial infarction. Also, the evidence suggests that dairy consumption, particularly low-fat dairy and yogurt is associated with a lower risk of type 2 diabetes. Likewise, moderate compared with medium consumption of dairy is associated lower risk for colorectal and bladder cancer and has no association with prostate cancer. Finally, consumption of milk or dairy products did not show a proinflammatory effect on healthy subjects, overweight/obese individuals, or individuals with other metabolic abnormalities, and fortification of dairy products with phytosterols and ω-3 fatty acids seems to be a good approach to improve cardiometabolic risk biomarkers. In conclusion, the systematic reviews and meta-analyses of the present supplement support adequate milk consumption at various stages of life and in the prevention/control of various noncommunicable chronic diseases.