Milk and dairy products: good or bad for human health? An assessment of the totality of scientific evidence

Background: There is scepticism about health effects of dairy products in the public, which is reflected in an increasing intake of plant-based drinks, for example, from soy, rice, almond, or oat. Objective: This review aimed to assess the scientific evidence mainly from meta-analyses of observational studies and randomised controlled trials, on dairy intake and risk of obesity, type 2 diabetes, cardiovascular disease, osteoporosis, cancer, and all-cause mortality. Results: The most recent evidence suggested that intake of milk and dairy products was associated with reduced risk of childhood obesity. In adults, intake of dairy products was shown to improve body composition and facilitate weight loss during energy restriction. In addition, intake of milk and dairy products was associated with a neutral or reduced risk of type 2 diabetes and a reduced risk of cardiovascular disease, particularly stroke. Furthermore, the evidence suggested a beneficial effect of milk and dairy intake on bone mineral density but no association with risk of bone fracture. Among cancers, milk and dairy intake was inversely associated with colorectal cancer, bladder cancer, gastric cancer, and breast cancer, and not associated with risk of pancreatic cancer, ovarian cancer, or lung cancer,while the evidence for prostate cancer risk was inconsistent.Finally,consumption of milk and dairy products was not associated with all-cause mortality. Calcium-fortified plant-based drinks have been included as an alternative to dairy products in the nutrition recommendations in several countries. However, nutritionally, cow’s milk and plant-based drinks are completely different foods,and an evidence-based conclusion on the health value of the plant-based drinks requires more studies in humans. Conclusion: The totality of available scientific evidence supports that intake of milk and dairy products contribute to meet nutrient recommendations, and may protect against the most prevalent chronic diseases, whereas very few adverse effects have been reported

Lipids and cardiovascular disease risks with a focus on dairy foods

Cardiovascular diseases (CVD) remain a major cause of death and morbidity worldwide and dietary guidelines aim to restrict the intake of saturated fatty acids (SFA) as they have been regarded as an important risk factor for CVD due to of their association with increased blood cholesterol. Since dairy foods are often the major contributors of dietary SFA, there have been guidelines to reduce consumption of these foods. However it is now generally accepted that the effects of dietary SFA are not simple and can be influenced by their source and food matrices. Also the effect of reducing SFA intake is best interpreted by a knowledge of what replaces them. Reduced CVD risk has been associated with replacement of SFA with cis-polyunsaturated fatty acids (cis-PUFA) and/or cis-monounsaturated fatty acids (cis-MUFA), with replacement by carbohydrate leading to no reduction or even increased CVD risk. Most studies on the effect of diet/food on CVD risk have used total cholesterol (TC) and/ or low density lipoprotein cholesterol (LDL-C) in blood as the marker(s) of risk. However, because of potentially attenuating effects of dairy foods (e.g. effect of protein on blood lipids and blood pressure; food matrix effects on fat bioavailability) a wider range of markers is needed to more fully evaluate disease risk. Nevertheless, whilst prospective evidence shows no increase in CVD risk from high dairy consumption, it is still uncertain whether replacing a proportion of SFA in dairy fat with cis-MUFA will consistently lead to reduced CVD risk. The relatively few randomised controlled trials (RCTs) that have examined this using TC and/or LDL-C as risk markers give an indications of benefit and the results of a recent RCT give stronger support to this