The Role of Milk Fat in Modern Human Nutrition: What Is the Current State of Knowledge?

Milk is a good source of fats and proteins as well as essential nutrients such as calcium and phosphorus. Milk has been an important part of the human diet since the domestication of animals. Milk consumption, particularly cow's milk, is at an all-time high in western societies, and steadily increasing in societies undergoing nutrition transition. Milk is regarded as an important component of a healthy diet especially during childhood and adolescence. In recent times, controversy abounds regarding the role of dairy products, especially dairy fat, in cardiovascular health as many recent studies have reported inconsistent findings. Here, we present a review of the current state of knowledge focusing on effects of milk fat and fatty acid compositions, biomarkers for fatty acid intake and microRNA in milk exosomes, on human health. We suggest that interdisciplinary approaches and trans-sectorial collaboration are needed to clarify the role of milk fat in human health. The quality and composition of milk fat can vary widely, even between individual animals in the same breed. Constraints and potential for modulation of milk fatty acid composition by nutritional and genetic strategies will be discussed. Finally, we propose that dairy foods, including regular-fat milk and other dairy products, can remain as an important component of an overall healthy dietary pattern for a majority of individuals across the lifespan.