A new Canadian study led by University of Toronto professor Harvey Anderson found that three servings of full-fat dairy a day did not worsen body weight, body composition, energy metabolism or blood lipid levels over 12 weeks. The results, published in The Journal of Nutrition, add to evidence that dairy fat may not behave the way long-standing advice has assumed.
The finding lands now because dairy has been pushed for years toward the low-fat end of the shelf. In Canada and many other countries, guidance has typically steered people away from fat-free or low-fat dairy on the belief that saturated fat in dairy products could raise cholesterol and cardiovascular risk. Anderson’s study puts that advice under fresh pressure by showing no harmful effect from full-fat dairy in 74 adults.
Researchers randomly assigned adults with overweight or obesity to three diets: a low-dairy, calorie-restricted plan; an energy-neutral plan with three daily servings of dairy; and an unrestricted diet that also included three daily servings. All participants were guided to follow Canada's food guide, and the dairy groups were supplied with full-fat dairy products during the study. After 12 weeks, there were no meaningful differences in weight gain, body composition or cholesterol levels between the low-dairy group and the people eating three servings of dairy each day. Those who consumed more dairy also took in more calcium, protein and vitamin D, and they showed improvements in blood pressure.
That does not erase the old concern. Dairy foods still contain saturated fat, and they have long been linked in nutritional advice to higher cholesterol and heart risk. But the results fit a broader pattern Anderson points to: full-fat dairy appears to act differently from saturated fat alone. He said people who had three servings of dairy did not have adverse levels of blood cholesterol or lipids, or signs of insulin resistance. In his view, that is part of the dairy matrix idea, where casein and whey are bound together with fat and other nutrients in a way that changes how the body handles them.
The study also leaves one important question open. Its findings are reassuring over 12 weeks, but they do not prove the same result would hold over a longer period. Anderson said the work may be especially important for older adults, who are often told to avoid dairy fat. For now, the clearer answer is that three servings of full-fat dairy did not harm the measured health markers in this group, even as the case for automatic low-fat dairy advice looks weaker.
