Whole milk dairy foods: Exploring the evolving science
While dietary guidance to choose foods low in saturated fat – including low-fat or fat-free milk, yogurt and cheese – has not changed in 30 years, the science is evolving.
The Dietary Guidelines for Americans have recommended limiting saturated fat intake, due to its links with heart disease and stroke risk related to increases in LDL-cholesterol. However, a growing body of evidence, including two new studies, indicates consumption of saturated fat and whole-milk dairy foods (i.e., milk, cheese and yogurt) may not be directly associated with an increased risk of cardiovascular disease (CVD).
A new randomized controlled trial of 17 healthy adults in Denmark found drinking about 2 cups of whole milk per day for three weeks did not negatively impact markers of CVD or Type 2 diabetes (T2D), compared to drinking fat-free milk. These factors included fasting blood levels of total and LDL-cholesterol, triglycerides, insulin and glucose. In addition, drinking whole milk increased HDL-cholesterol compared to fat-free milk.
Evidence from a recently published systematic review of older prospective cohort studies aligns with newer evidence showing that consumption of saturated fat may not be associated with a greater risk of CVD. This review of older studies focused on total dietary fat, saturated fat and death from coronary heart disease – and found few relationships.
These results align with evidence from observational, systematic reviews and meta-analysis of showing that dairy foods, regardless of fat content, have a neutral association with risk for cardiovascular health. In fact, two clinical trials published in 2016 found no differences in heart disease or T2D risk factors when eating whole milk, cheese and yogurt or only full-fat cheese when compared with eating lower-fat varieties in adults. This may be due to one or more unique characteristics of the dairy food group (milk, cheese and yogurt), including its combination of milk’s nine essential nutrients, the unique fatty acid profile of dairy fat, or how the structure (i.e., food matrix) of milk, yogurt or cheese interacts with the other foods.
Though scientists have not reached a consensus on the role of whole-milk dairy foods and health, research suggests that for healthy adults, whole milk, regular cheese and whole milk yogurt can be part of a calorie-balanced, healthy eating plan. Perhaps, emerging research will lead to more flexibility in food choices.