Milk and meat in our diet: good or bad for health?

Abstract

Foods derived from animals are an important source of nutrients in the diet but there is considerable uncertainty about whether or not these foods contribute to increased risk of various chronic diseases. For milk in particular there appears to be an enormous mismatch between both the advice given on milk/dairy foods items by various authorities and public perceptions of harm from the consumption of milk and dairy products, and the evidence from long-term prospective cohort studies. Such studies provide convincing evidence that increased consumption of milk can lead to reductions in the risk of vascular disease and possibly some cancers and of an overall survival advantage from the consumption of milk, although the relative effect of milk products is unclear. Accordingly, simply reducing milk consumption in order to reduce saturated fatty acid (SFA) intake is not likely to produce benefits overall though the production of dairy products with reduced SFA contents is likely to be helpful. For red meat there is no evidence of increased risk of vascular diseases though processed meat appears to increase the risk substantially. There is still conflicting and inconsistent evidence on the relationship between consumption of red meat and the development of colorectal cancer, but this topic should not be ignored. Likewise, the role of poultry meat and its products as sources of dietary fat and fatty acids is not fully clear. There is concern about the likely increase in the prevalence of dementia but there are few data on the possible benefits or risks from milk and meat consumption. The future role of animal nutrition in creating foods closer to the optimum composition for long-term human health will be increasingly important. Overall, the case for increased milk consumption seems convincing, although the case for high-fat dairy products and red meat is not. Processed meat products do seem to have negative effects on long-term health and although more research is required, these effects do need to be put into the context of other risk factors to long-term health such as obesity, smoking and alcohol consumption.Keywords: milk, meat, chronic disease, animal nutrition ImplicationsIncreasing obesity and an ageing population increase the risk of chronic disease and its associated financial cost substantially. Diet is a modifier of risk and since milk, meat and their products are staple components of most Western diets, it is very important to understand whether these foods increase or decrease the risk of chronic disease. Milk appears to provide some worthwhile reduction in risk of cardiovascular disease and colorectal cancer and while this needs further understanding, the implications for milk production and milk consumers are potentially very substantial. There remains uncertainty about the effects of red meat and processed meat in the diet and these need urgent clarification both for the consumer and the producer. IntroductionPublic health nutrition is facing multiple and major challenges. In particular, there are three m...

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