Role of fatty acids of milk and dairy products in cardiovascular diseases: A review

Abstract

There are increasing global concerns about the role of foods in health and chronic diseases. Milk and dairy products are important sources of dietary protein and fat in the diets of many cultures including African communities. However, questions are being raised concerning the role of milk-nutrients in chronic diseases including CVDs. Also, the African public often does not have access to scientific information on the nutritional and health significance of nutrients in some of their major foods including milk and dairy products. This review of the literature was therefore conducted in order to provide information on the role of the fatty acids of milk and dairy products in respect of CVDs, with reference to some African communities. The fatty acids linoleic and alpha-linolenic are precursors of eicosanoids, whose excessive and/or imbalanced synthesis has been implicated in various pathological conditions including CVD. Due to the considerable amount of saturated fatty acids and cholesterol in milk, its consumption is often associated with mortalities from CVDs. Myristic and lauric acids are atherogenic, and raise the risk of CVD by increasing plasma cholesterol and LDL, although oleic, linoleic and linolenic reduce the increase. Palmitic acid does not seem to be strongly atherogenic, while stearic acid is largely neutral. Abundant intake of saturated fats increases plasma LDL and VLDL. Although considered high cholesterol foods, milk and dairy products may not be major contributors of dietary cholesterol, as whole milk contains 10-15 mg  cholesterol/dL, while skimmed milk with 1% butter-fat contains less than 8 mg/dL cholesterol. Trans fats have been implicated as risk factors for CVD due to their  hypercholesterolemic effect. The risks of CVD from trans fats intake in milk and its products are, however, lower compared to risks from the consumption of  hydrogenated vegetable oils. Linoleic, α-linolenic and oleic acids are considered cardioprotective. The short and medium-chain fatty acids do not seem to influence plasma cholesterol levels; monounsaturated fats tend to have a neutral influence, while polyunsaturated fats tend to lower total cholesterol, but may also lower the “good” HDL. To lower cholesterol and saturated fatty acids intake from milk and dairy products, and to slow atherosclerosis progression, it is recommended that the consumption of full-fat milk be reduced while increasing that of skimmed milk and cheese. This can be achieved by integrating these findings into food processing practices, agricultural, and nutritional policy in Africa.

Keywords: Milk, Diet, Fat, Fatty acids, Cholesterol, Cardiovascular diseases