New Study Challenges Decades-Old Advice to Choose Low-Fat Dairy Products

Your morning glass of full-fat milk may not be the dietary villain it was once made out to be.

A new Canadian study is challenging decades of low-fat advice, finding that three servings of full-fat dairy a day did not worsen body weight, body composition, cholesterol, or energy metabolism—and may even provide some health benefits.

Published in The Journal of Nutrition, the 12-week study included 74 adults with overweight or obesity. Participants were randomly assigned to different dietary approaches, including a calorie-restricted low-dairy diet, an energy-neutral diet containing three daily dairy servings, or an unrestricted diet with three servings of dairy.

After 12 weeks, researchers found no meaningful differences in weight gain, body composition, or blood lipid levels between participants eating three servings of dairy and those following the low-dairy approach. Importantly, the higher-dairy groups did not develop harmful cholesterol levels or signs of insulin resistance.

There was also a nutritional upside. Participants consuming more dairy showed improvements in blood pressure and consumed greater amounts of calcium, protein, and vitamin D.

Why might full-fat dairy behave differently from what its saturated-fat content suggests? Researchers point to the “dairy matrix” hypothesis. Dairy is not simply a collection of individual nutrients; proteins, fats, minerals, and other components are structurally packaged together. This matrix may influence how nutrients are digested and absorbed, potentially changing their effects on health.

The findings could be particularly relevant for older adults, who often need nutrient-rich foods such as protein and calcium while managing lower energy requirements.

However, the study was relatively small and lasted only 12 weeks, so it cannot settle the long-term cardiovascular question. For now, the researchers suggest focusing less on demonizing individual nutrients and more on overall dietary patterns.

In other words: eat a variety of foods, keep portions sensible—and perhaps stop treating full-fat dairy like the enemy.

REFERENCE: Gerald Harvey Anderson, et al.; The Effect of Three Daily Servings of Full-Fat Dairy for 12 Weeks on Body Weight, Body Composition, Energy Metabolism, Blood Lipids, and Dietary Intake of Adults with Overweight and Obesity. The Journal of Nutrition, 2026; 156 (4): 101373 DOI: 10.1016/j.tjnut.2026.101373