If you’re hankering for a cool treat on a hot day, nothing screams summer like ice cream.

And a physician renowned for shaping U.S. healthcare policy has a message: Go ahead and enjoy it.

Zeke Emanuel is an oncologist and bioethicist who served as an advisor to the Obama administration, helping shape the Affordable Care Act. He believes in a system that invests in prevention, one that aims to keep people healthy. So when he released his book, literally titled Eat Your Ice Cream: Six Simple Rules For A Long And Healthy Life, I asked him what motivated him.

“Mostly anger at the wellness industrial complex,” Emanuel told me. He says the wellness industry is selling people all kinds of things that are expensive and clinically unproven, pointing to the latest peptide trend, whole body scans and “all sorts of supplements” marketed as anti-aging elixirs.

Emanuel takes a back-to-basics approach, based on evidence, to maintain good health in his book.

And though the title is a bit tongue-in-cheek, he points to evidence that people who are in the habit of eating ice cream have a lower risk of metabolic disease, despite the fact that it has lots of sugar and fat. Researchers have dubbed this the “ice cream paradox.” There’s data from 2015 that suggests “that ice cream is actually pretty good at preventing development of type two diabetes, and dairy in general is good at preventing type two diabetes,” Emanuel says.

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Dairy contains whey protein that may benefit glucose regulation which may partially explain the association, though the research doesn’t nail down cause and effect. Emanuel is also big on consuming more fiber and fermented foods, pointing to the need to feed the bacteria in our guts.

“Evolution would have gotten rid of them if they weren’t there for a reason,” Emanuel says. “And so treating them well, through eating more fermented foods, whether it’s yogurt or cottage cheese or hard cheeses like gruyere or kimchi or sauerkraut, good things for us.”