3 Sour Foods With Major Health Benefits

Long associated with serrated spoons and deprivation diets (Joan on Mad Men was a fan), the sour, zingy citrus deserves a spot on your plate. A 2014 lab study at the University of California, Berkeley, found that grapefruit juice not only helped animals lose 18 percent more weight than those that drank just water, but also lowered their blood glucose as effectively as the type 2 diabetes drug metformin. If you have a choice of yellow or pink, go for the later: A ruby-hued grapefruit provides about a fifth of your daily vitamin A needs (critical for vision and skin) and contains lycopene, the pigment that lends tomatoes their potentially heart-protecting properties. One word of caution: Grapefruit can interfere with certain medications, so check with your doctor before adding it to your diet.

These juicy jewels, with their trademark sour-sweet flavor, get their color from anthocyanins, potent anti-inflammatory compounds. Tart cherry juice has been shown in several studies to reduce postexercise muscle soreness and significantly decrease exercise-induced inflammation, lessening muscle damage and recovery time. And researchers have found that it can lower the amount of uric acid in the blood -- by as much as 36 percent, which suggests it may soothe inflammatory conditions like gout and osteoarthritis.

Yogurt gets a lot of attention for its high levels of good-for-you bacteria, but kefir, a creamy dairy drink, can contain up to six times more probiotics. "The live cultures of bacteria and yeast responsible for its health benefits are also what give kefir its tanginess," says Sass. Extensive research has found that regular consumption of the probiotics found in kefir may ease hay fever symptoms (probiotic bacteria can stabilize the gut's environment and promote the release of antiallergic immune factors) as well as inhibit the growth of bad bacteria like E. coli, potentially helping to prevent infections. Kefir can take getting used to -- some find it too sour -- so try mixing it with fresh berries, adding a little honey or masking the tartness by blending it into fruit smoothies.