For decades, dietary advice steered people toward low-fat dairy. A new randomized trial adds to a growing body of evidence questioning that — though its size, length and funding call for caution.
Researchers at the University of Toronto, led by nutrition professor Harvey Anderson, ran a 12-week randomized controlled trial in 74 adults with overweight or obesity. Participants followed one of three diets: low-dairy with calorie restriction; an energy-neutral diet with three daily dairy servings; or an unrestricted diet with three daily servings. Crucially, most of the dairy was full-fat.
What they found
Full-fat dairy did not worsen weight, body composition, or cholesterol and lipid levels; those eating three servings a day even showed improved blood pressure and higher intake of calcium, protein and vitamin D. “Those that had three servings of dairy didn’t have adverse levels of blood cholesterol or lipids or evidence of insulin resistance,” Anderson said. Researchers point to the “dairy matrix” idea — that the way dairy’s fats, proteins and nutrients are packaged together affects the body differently than isolated saturated fat.
Read it with caution
Two caveats matter. The study was short (12 weeks) and limited to adults with overweight or obesity, so it can’t speak to long-term heart-disease risk or other groups. And it was funded by dairy-industry sources (Dairy Research Cluster 3), a conflict of interest to weigh. It adds to the case that full-fat dairy may not be the villain it was once thought — but it isn’t the final word.
This article summarizes one short study and is not dietary or medical advice. Talk to a qualified professional about your own nutrition and health.