New perspectives on dairy and cardiovascular health
The Nutrition Society Paper of the Month for July is from the Proceedings of the Nutrition Society and is entitled ‘Milk and dairy produce and CVD: new perspectives on dairy and cardiovascular health’ Authors Julie A. Lovegrove and Ditte A. Hobbs present the key findings of their paper below.
Meta-analysis of large cohort studies has identified inverse associations between milk consumption and stroke, and overall CVD risk, with no effect on coronary heart disease risk. While this may seem counter-intuitive with respect to the high SFA content of these foods, new research suggests that other components within dairy products may be reducing the negative effects of the SFA on cardiovascular health. In relation to the total fat content of dairy foods, there is insufficient comparative data on the effects of whole and low-fat dairy products, to support any consensus on whether lower fat dairy products are healthier. There is some evidence that lower fat dairy foods may be more beneficial in terms of reducing CVD risk, though this requires confirmation in randomly controlled human intervention studies.
In epidemiological studies, a high intake of dairy has also been associated with lower levels of key biomarkers of CVD, most notably hypertension. This finding has been reinforced by evidence from randomly controlled dietary intervention studies that milk, and specifically milk proteins, can lower blood pressure. There are also supportive mechanistic data that milk proteins and bioactive peptides can regulate blood pressure, possibly through inhibition of a key modulator of high blood pressure, angiotensin converting enzyme (ACE).
Dairy products are known to contain other bioactive components, including calcium, which in addition to a favourable effect on blood pressure may limit the serum cholesterol-raising response of certain dairy products (excluding butter) that would be predicted from their SFA content alone. In this respect, the excretion of SFA as calcium containing soaps is emerging as a potential mechanism for lower SFA absorption and explains in part, the lower cholesterol response.
Current evidence indicates that milk and dairy products (excluding butter) are not associated with detrimental effects on CVD risk, and may exert benefits to cardiovascular health. Therefore, exclusion of milk, cheese and yoghurt should be contraindicated as a strategy for the primary prevention of CVD in populations.
The paper is freely available via the following link: http://journals.cambridge.org/ns/jul16 until 7th August 2016.
Nutrition Society Paper of the Month
Each month a paper is selected by one of the Editors of the five Nutrition Society Publications (British Journal of Nutrition, Public Health Nutrition, Nutrition Research Reviews, Proceedings of the Nutrition Society and Journal of Nutritional Science).