What kind of dairy does a body good? Science is updating the answer

When new dietary guidelines are unveiled later this month, the Trump administration is expected to upend long-held advice on whole milk and its full-fat friends in the dairy aisle.

For decades, the American public has been advised to opt for fat-free or low-fat dairy options, largely out of concern for limiting the intake of saturated fat in these foods.

While the public doesn’t necessarily follow this advice — cheese is the leading source of saturated fat in our diet — Health Secretary Robert F. Kennedy has promised to end the “attack on whole milk, cheese and yogurt” and give these foods new prominence in the forthcoming guidelines.

So, what’s the case for ditching skim milk and other low-fat alternatives?

Richard Bruno, a professor of human nutrition at the Ohio State University, says the field of nutrition has wrestled over this question for many years.

“There’s been a lot of controversy,” says Bruno, who has authored numerous studies on the topic.

Views have evolved in recent years as researchers have started to learn “the saturated fat from dairy foods doesn’t seem to be behaving the way we think it should behave, based on the historical evidence that saturated fat is linked to heart disease,” he says.

Because dairy is such a broad category — and fat content varies widely between foods like milk, yogurt and cheese — it’s challenging to make sweeping statements. Yet, Bruno and others in the field say once you dig into the data, the rationale for an across-the-board recommendation to favor skim milk and low-fat dairy quickly falls away.

“If we are saying that low fat is better than high fat, we should have studies demonstrating that, black and white, because guidelines should be evidence-based,” says Benoît Lamarche, who directs the Nutrition, Health and Society Center in Quebec and is a professor at Université Laval.

That’s why Lamarche pulled together leaders in the field of nutrition last year, including several who had worked on dietary guidelines, to pour over the evidence on dairy fat and its link to cardiometabolic health.

Their conclusion?

“The evidence is showing that they have the same effect and the evidence is of low quality and there’s just a few studies that have looked at that,” he says.

Lamarche says the argument against full-fat dairy is largely “circumstantial.”

Earlier research showed people who were at a higher risk of heart disease tended to have a dietary pattern that included more full-fat dairy, but there were other factors — and foods in their diet— that could explain this finding.

“We don’t have the strict and rigorous evidence opposing the two types of dairy and their effect on health,” he says. “We need to stop distracting people with this recommendation.”

Some recent studies have even signaled that consuming higher-fat dairy is not only neutral, but, in some cases, may also carry benefits beyond low-fat options, at least when part of a healthy eating pattern.

One small trial found that participants who followed the “DASH” diet — developed by scientists at the National Institutes of Health to lower hypertension — and substituted high-fat dairy had comparable improvements in blood pressure as those who ate low-fat dairy and better blood lipid levels, which is a risk factor for heart disease.

Another study that followed 18 adults in Europe for three weeks found drinking whole milk actually outperformed skim milk when it comes to raising HDL, or “good” cholesterol.

Bruno says the hypothesis is that certain bioactive components in the milk fat membrane like phospholipids “alleviate any putative risks that would be associated with that higher intake of saturated fat.”

The key, he says, seems to be how the dairy fat is delivered.

For example, research shows butter — also derived from dairy but primarily composed of fat and water — has the predicted negative consequences on cholesterol; however, that’s not true when people consume the same amount of saturated fat in the form of cheese, which comes with calcium, protein, minerals and other components.

In fact, Lamarche notes there’s strong evidence from observational studies that cheese is associated with a lower risk of stroke.

“Is this real or confounded by something else?” he says. “We don’t know, but the data is quite consistent on this.”

Likewise, there’s a well-documented link between yogurt and the prevention of Type 2 diabetes, which led the Food and Drug Administration to issue a health claim on those products (though, of course, the universe of yogurt encompasses everything from whole milk Greek yogurt to sugar-loaded nonfat varieties).

While some recent trials examining higher-fat dairy products show promise, Bruno believes it’s “premature to have a one-size-fits-all recommendation that consumers should favor full fat versus nonfat.”

Even when it comes to milk, the evidence is slim in either direction, and Lamarche argues that guidance in the U.S. and Canada should be agnostic on the question for now, until there’s better data.

In its reports, the scientific advisory committee that provides guidance for the federal government on the 2025 dietary guidelines decided not to change the existing recommendations in support of low-fat milk because it “could not draw a conclusion about the relationship between consumption of milk with different fat content” — advice that Kennedy may very well ignore given his public comments disparaging the scientific report.

Frank Hu, chair of the department of nutrition at the Harvard T.H. Chan School of Public Health, agrees there still aren’t clear answers, meaning there’s no reason to start promoting full-fat dairy as superior, especially since a glass of whole milk and cheese comes with more overall calories and saturated fat.

In his mind though, the much bigger problem is that Americans are mostly consuming dairy products in the form of pizza, burgers, sandwiches and other foods that are “loaded with sodium, refined starch and processed meats.”

In that context, it probably doesn’t make much difference if the cheese you are eating is low fat or high fat. On the other hand, it’s relatively easy to “incorporate a moderate amount of dairy into your overall diet whether it’s full fat or low fat,” he says.

“If you’re replacing your carbohydrates, especially refined carbohydrates and sugar, with dairy products, even some full-fat dairy products, that’s probably a good thing.”