Dairy consumption of around three servings per day is associated with lower rates of cardiovascular disease and mortality, according to a groundbreaking study of over 130,000 people in 21 countries.
The findings are consistent with previous analyses of observational studies and randomised trials, but stand in contrast to current dietary guidelines which recommend consuming 2-4 servings of fat-free or low-fat dairy per day, and minimising consumption of whole-fat dairy products for cardiovascular disease prevention. Cardiovascular disease is the leading cause of mortality worldwide, with an estimated 685,000 people living with heart and circulatory diseases in Scotland.
The authors of the study, published in The Lancet conclude the consumption of dairy should not be discouraged and should even perhaps be encouraged in low-income and middle-income countries where dairy consumption is low.
Lead author Dr Mahshid Dehghan, McMaster University, Canada, said: “Our findings support that consumption of dairy products might be beneficial for mortality and cardiovascular disease, especially in low-income and middle-income countries where dairy consumption is much lower than in North America or Europe.”
The Prospective Urban Rural Epidemiological (PURE) study included data from 136,384 individuals aged 35-70 years in 21 countries. Dietary intakes were recorded at the start of the study using country-specific validated food questionnaires. Participants were followed up for an average of 9.1 years. During this time, there were 6,796 deaths and 5,855 major cardiovascular events. One standard serving of dairy was equivalent to a glass of milk at 244g, a cup of yoghurt at 244g, one slice of cheese at 15g, or a teaspoon of butter at 5g. Dairy consumption was highest in North America and Europe (368g/day or above 4 servings of total dairy per day) and lowest in south Asia, China, Africa and southeast Asia (147, 102, 91 and 37g/day respectively – less than 1 serving of total dairy per day).
The authors say that more research into why dairy might be associated with lower levels of cardiovascular diseases is now needed. The recommendation to consume low-fat dairy is based on the presumed harms of saturated fats on a single cardiovascular risk marker (LDL cholesterol). However, evidence suggests that some saturated fats may be beneficial to cardiovascular health.