RFK Jr., nutrition: Is whole milk healthy?

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Robert F. Kennedy Jr. sure loves whole milk. Last fall, his health administration declared that the “war” on whole milk was over. More recently, he posted an A.I.-generated video of himself drinking whole milk and dancing, his upper lip adorned with a milk mustache. His new dietary guidelines prominently recommend whole milk. Specifically, the guidelines advise that Americans should eat three servings of “full-fat” dairy each day: “Dairy is an excellent source of protein, healthy fats, vitamins, and minerals.”

From a scientific standpoint, that full-fat dairy recommendation is odd. Virtually all milk that you can buy in a supermarket is essentially the same. It has been made to be the same. Given the MAHA fixation on whole milk, you’d be forgiven for thinking that full-fat dairy has more vitamins and minerals than skim, or more protein. It does not. All it has is more fat.

Let’s back up: When it comes to the actual production of milk, each cow is different, and provides a different ratio of milk to cream on different days. In addition, if you milk a cow and then leave the milk entirely as-is, you end up with a thick cap of cream on top, which has to be stirred in if you don’t want to have globules of fat dissolving on your tongue as you drink it. (Speaking from experience: It’s kind of gross. I had a fair bit of nonhomogenized milk in my childhood, and there is nothing worse than a large glob of fat landing on your cereal in the morning because you forgot to stir the milk.)

The solution to the problem is called homogenization, in which a high-pressure device evenly spreads the fat content throughout the milk, ensuring that by the time a gallon of milk reaches you, the cream won’t be in a layer at the top. It also evenly distributes the fat, making every mouthful taste and feel the same. The difference between whole and 1 percent and skim is just the amount of fat (aka cream) that’s in the milk.

But, aside from the fat percentage, any kind of milk you’re buying is essentially identical regardless of the fat percentage. One percent milk has the same protein, vitamins, and minerals as whole. You—and perhaps RFK Jr.—might think that whole milk is at least more “natural,” given that “whole” is in its name. But it’s not. Virtually all milk available at supermarkets has been processed. That’s a good thing.

What whole milk does have more of is fat—specifically, saturated fat. The secretary of the Department of Health and Human Services loves saturated fat, and has publicly encouraged everyone to eat more of it. There is a strong causal link between saturated fat intake and heart health. It’s arguably the strongest nutritional finding that I know of as an epidemiologist who enjoys looking into these things: Eating saturated fat increases bad cholesterol. Bad cholesterol causes cardiovascular disease. Reducing bad cholesterol prevents cardiovascular disease. Therefore, eating less saturated fat likely prevents issues such as heart attacks. Preventing heart attacks is healthy.

Weirdly, RFK Jr.’s new dietary guidelines agree with this scientific finding. They recommend limiting your saturated fat intake to 10 percent of your calories, which is broadly consistent with prior nutritional advice. That sensible recommendation clashes with the guidelines’ recommendation on full-fat dairy, and with RFK Jr.’s public affection for whole milk. If you were to drink whole milk for your three daily servings of dairy, you’d be close to meeting your saturated fat intake from the milk alone. Getting close to the daily recommended saturated fat limit by drinking whole milk isn’t bad per se; it just means you’d need to watch your saturated fat intake otherwise, something RFK Jr. doesn’t seem particularly intent on doing. For example, it’s essentially impossible to follow the guidelines for full-fat dairy, and the 10 percent recommendation for saturated fat, and use RFK Jr.’s beloved beef tallow to cook your food.

In addition to implying that whole milk has more nutrients, RFK Jr.’s argument is that replacing whole milk with skim and other low-fat milk options has led to kids drinking more sugary drinks instead of milk. Basically: Without access to whole milk, kids will load up on sugary beverages. Sure, drinking a lot of soda or even chocolate milk is unhealthy. But that’s not a reason to recommend whole milk. It’s a bit like saying that people are replacing Tylenol with oxycodone, so you’re giving everyone aspirin instead. We don’t really know if emphasizing whole milk is healthier, in the end. The best current evidence suggests that there may be some benefit—although, in my opinion, a small one—from drinking lower-fat options instead. You shouldn’t eat a lot of saturated fats, generally, but choosing one kind of milk or another to pour in your cereal probably won’t make that much of a difference.

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The scientific foundation for the guidelines actually acknowledges that whole milk might not be healthier. The appendix notes: “We need definitive RCT data to determine whether whole-fat dairy intake will improve the metabolic health of American children.” RCT stands for “randomized controlled trial.” That is, a study to show if drinking whole milk is actually healthier—the sort of thing that you usually commission before changing the guidelines in confusing ways.

So: Should you drink whole milk or skim? Having looked at the evidence, I don’t think that there’s a strong argument either way here. Whole milk is essentially the same product as lower-fat options. The only difference is that you get a little bit more fat, but there’s no strong data showing that the fat is good or bad for you. It’s a few more calories, but the difference isn’t that huge—if you’re drinking 1 percent milk, those three cups will be about 300 calories, versus 450 if you go for whole milk. You’ll be getting a bit more saturated fat as well, which isn’t ideal, but in the quantities in milk, is also unlikely to have a dramatic impact on your health. Everyone agrees that chocolate milk is terrible for your health. If you’re trying to lose weight or lower your cholesterol, skim milk is better than full-fat. Beyond that, from a scientific standpoint, there doesn’t seem to be a strong reason to recommend one type of milk over another.

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