For Years, We Were Told To Choose Low-Fat Dairy: New Research Disagrees

For many years, health guidelines have advised people to consume low-fat or fat-free dairy products, claiming that the saturated fat present in whole milk, cheese, and yogurt could elevate cholesterol levels and negatively impact heart health. However, a recent study from the University of Toronto has challenged this conventional wisdom, discovering that daily consumption of full-fat dairy for 12 weeks did not lead to any adverse effects on weight, body fat, cholesterol, or heart health markers among adults.

The research, published in The Journal of Nutrition, was led by Professor Harvey Anderson and supported by Dairy Research Cluster 3 under the Canadian Agricultural Partnership AgriScience Program.

The study involved 74 participants classified as overweight or obese. These individuals were divided into three groups: one followed a low-dairy, calorie-restricted diet, another adhered to an energy-neutral diet incorporating three servings of dairy daily, and the third followed an unrestricted diet with the same daily dairy intake. All participants followed Canada's food guide, and those in the dairy groups were provided with full-fat dairy products throughout the study period.

Surprisingly, the results showed no significant increase in weight, body fat, cholesterol, or insulin resistance among those consuming full-fat dairy compared to the low-dairy group. Moreover, participants who ate full-fat dairy had better blood pressure readings and increased their intake of calcium, protein, and vitamin D.

Professor Anderson suggests that the structure of dairy products, containing two proteins—casein and whey—bound together with fat and various nutrients, may be responsible for the observed benefits. He explains that this complex physical structure facilitates a slow, steady release of nutrients, potentially contributing to a broader range of health benefits beyond the isolated nutrients.

Dietitian Jessica Corwin commented on the findings, acknowledging their importance in providing a nuanced perspective on dietary advice. She notes that the study does not definitively prove that full-fat dairy is healthier than low-fat dairy, but it does contradict the assumption that adding full-fat dairy to a healthy diet would lead to weight gain or worsen heart-related health markers.

Corwin emphasizes the broader lesson that nutrition science teaches us: we cannot always predict the health effects of a whole food by examining its isolated nutrients. Dairy contains saturated fat, but it also provides high-quality protein, calcium, potassium, and other essential nutrients within a complex food matrix. She concludes by advocating for whole foods as the optimal choice over single-nutrient supplements.