Should it be?

It all happened quickly. In the 1990s, during the original “Got Milk?” campaign, it was plausible to look at a magazine, see supermodels with dairy-milk mustaches, and think little of it. Now many people would cry foul. With nut milks dominating the luxury café-grocery scenes frequented by celebrities, an image like that would surely elicit cries of disingenuousness: There’s no way you actually drink cow’s milk! And if you do, it’s probably skim or 2-percent milk, which leave no such thick mustache!

Difficult as it may be for Millennials to imagine, the average American in the 1970s drank about 30 gallons of milk a year. That’s now down to 18 gallons, according to the Department of Agriculture. And just as it appears that the long arc of American beverage consumption could bend fully away from the udder, new evidence is making it more apparent that the perceived health risks of dairy fats (which are mostly saturated) are less clear than many previously believed.

A new study this week in The American Journal of Clinical Nutrition is relevant to an ongoing vindication process for saturated fats, which turned many people away from dairy products such as whole milk, cheese, and butter in the 1980s and ’90s. An analysis of 2,907 adults found that people with higher and lower levels of dairy fats in their blood had the same rate of death during a 22-year period.

The implication is that it didn’t matter if people drank whole or skim or 2-percent milk, ate butter versus margarine, etc. The researchers concluded that dairy-fat consumption later in life “does not significantly influence total mortality.”

“I think the big news here is that even though there is this conventional wisdom that whole-fat dairy is bad for heart disease, we didn’t find that,” says Marcia de Oliveira Otto, the lead researcher of the study and an assistant professor of epidemiology, human genetics, and environmental science at the University of Texas School of Public Health. “And it’s not only us. A number of recent studies have found the same thing.”

Hers adds to the findings of prior studies that also found that limiting saturated fat is not a beneficial guideline. While much similar research has used self-reported data on how much people eat—a notoriously unreliable metric, especially for years-long studies—the current study is noteworthy for actually measuring the dairy-fat levels in the participants’ blood.

A drawback to this method, though, is that the source of the fats is unclear, so no distinction can be made between cheese, milk, yogurt, butter, etc. The people with low levels of dairy fats in their blood weren’t necessarily dairy free, but they may have been consuming low-fat dairy. All that can be said is that there was no association between dairy fats generally and mortality.