Milk, the stuff of childhood. Some of us drink it as adults, some might not, but it’s got a reputation for being a staple of our early years. Which is why parents have long used the advice of the American Academy of Pediatrics and eventually moved from giving their kids whole milk to reduced-fat milk, for health reason. But is that really the healthier choice?

A new study questions one of the traditional ways of doing things, which makes sense  — reducing fat cuts down on cholesterol and calories — but perhaps is just an assumption of being the healthy choice.

According to NPR, a study of preschool-aged kids published in the Archives of Disease in Childhood, a sister publication of the British Medical Journal, finds that low-fat milk was associated with higher weight. Which, low-fat milk was doing the opposite of what it was assumed to do.

“We were quite surprised” by the findings, the coauthor told NPR. Both he and his co-author pretty much figured the opposite would happen.

Instead, the connection between skim-milk drinkers and having a higher body weight worked across the board in all racial/ethnic and socioeconomic groups. The researchers add that low-fat milk didn’t keep preschoolers from gaining weight over time, a good thing as kids need grow.

Other studies have come up with similar results in different age groups, and involving other health quantifiers like body mass index.

So how can higher fat lead to lower weight? The two don’t seem to mix, but the researchers have a theory: whole milk makes us feel fuller and thus, content. No room for dessert!

“This is speculative,” says one author, but if you feel fuller after drinking whole-fat milk, “it may be protective if the other food options are high in calories.”

Before any kind of formal recommendation is made to change things up, the researchers think more studies should be done. To that point, critics point out things like the fact that in the study, kids on low-fat milk were already heavier in the first place.

All in all, drinking milk of any kind is going to be better for a kid than 32 ounces of Mountain Dew daily. So there’s that.

Whole Milk Or Skim? Study Links Fattier Milk To Slimmer Kids [NPR]

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