If you eat healthy, new research might come as a shock: You’re doing it all wrong.
That's right: Even if you opt for whole foods packed with vitamins and minerals, simple mistakes in the kitchen could be sapping them of their health benefits. Heat, water, storage, and exposure to air can all cause certain foods to lose their nutrients in different ways, says Mary Cluskey, Ph.D, R.D., associate professor of nutrition at Oregon State University.
So how do you make sure you’re getting the most out of your favorite foods? We collected five common mistakes that zap nutrients—and fast fixes that will ensure they pack a health-improving punch.
Vegetables
Your mistake: Microwaving or boiling them
The fix: Steam them
Why it works: Steaming helps retain cancer-fighting nutrients in broccoli better than other cooking methods, reports a new study from the University of Illinois at Urbana-Champaign. Sulforaphane—a plant compound with strong anti-cancer properties—is abundant in cruciferous vegetables like broccoli, cauliflower, kale, and arugula. The enzyme myrosinase is necessary to release the compound, but most cooking methods destroy it. Steaming is a slower, gentler heat, and isn’t intense enough to kill myrosinase, explains study author Elizabeth Jeffery, Ph.D. Cook broccoli in a steaming basket for 3 to 4 minutes for the biggest cancer-fighting boost.
Strawberries
Your mistake: Slicing them before eating
The fix: Eat them whole
Why it works: Whole strawberries contain 8 to 12 percent more vitamin C than the cut fruits, according to a 2011 Brazilian study. That’s because vitamin C begins to break down when it’s exposed to light and oxygen. For the biggest C boost, store whole strawberries in the fridge—cool temperatures help retain vitamin C too, finds the same study.
Wine
Your mistake: Letting a bottle “breathe"
The fix: Pour and enjoy
Why it works: When red wine is decanted for long periods of time—up to 12 hours—the organic acids and polyphenols begin to break down, according to a 2012 Chinese study. Leaving the bottle open overnight nixes the usual benefits of a glass of red, including decreased depression, increased testosterone, and a healthier heart.
Tomatoes
Your mistake: Eating them raw
The fix: Heat them up
Why it works: Tomatoes may lower your risk of stroke, fight prostate cancer, and preserve brain power as you age—that's why they made our list of the 40 Foods with Superpowers. But heating tomatoes significantly increases their levels of lycopene, the chemical that can raise antioxidant levels. In fact, a recent study in The British Journal of Nutrition found that raw foodists—people who eat mostly uncooked produce—were deficient in lycopene. Cook tomatoes in olive oil for the biggest nutritional boost: Lycopene is fat-soluble, meaning you need fat in your diet for your body to absorb it properly.
Frozen Produce
Your mistake: You skip right over frozen foods at the grocery store
The fix: Stop and shop
Why it works: “Most people think only fresh is healthy, but this is a huge misconception,” says Cluskey. In fact, U.K. scientists found that in two out of three cases, frozen fruits and vegetables packed higher levels of antioxidants—including polyphenols, vitamin C, and beta-carotene—than the fresh kind. As produce ages, nutrients begin to change and break down, says Cluskey. It's therefore better to eat food that was frozen at prime ripeness with its nutrients intact than week-old produce that no longer has the same beneficial chemical makeup.
