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The Other Great Source of Good-for-You Bacteria

We're talking about: Kefir
Why you should eat drink more of it: Probiotics are linked to everything from weight loss to lower blood pressure, says Sowa. You could reach for yogurt, but kefir is another good option (and something you can consume on the go). The fermented dairy drink can strengthen the immune system and potentially lower your risk of cancer, found one review in the Brazilian Journal of Microbiology.
Keep this in mind too: Kefir contains lactose, but don't worry if the natural sugar doesn't always agree with your stomach. The bacteria in kefir help your body digest it, and research suggests that over time they may help you better tolerate the lactose in other dairy products too.