by Stephanie Clarke, R.D., and Willow Jarosh, R.D., for SHAPE.com
You grind in the gym every day to look and feel your best, but if your diet doesn't include these 12 power foods, you're doing yourself and your health a disservice!
To strengthen bones: parmesan cheese
Calcium is key for preventing osteoporosis (especially in your 20s). Yogurt and nonfat milk help, but who wants them three times a day? Work Parmesan cheese into your diet; its 340 mg of calcium per ounce - compared to about 200 mg in cheddar or Swiss - goes a long way toward your 1000 mg/day quota.
To boost immunity: apples
Smart and sweet, apples are rich in quercetin, an antioxidant that can bolster your body's disease-fighting abilities. In one study from Appalachian State University, just 5 percent of people who ate more quercetin came down with a respiratory infection over a two-week period, compared to 45 percent of those who didn't.
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To build your iron stores: lentils
Low-calorie lentils pack about 30 percent of your daily iron per cup cooked. About 12 percent of young women have low iron stores - at the extreme, that leads to anemia. But one study found that even women who were iron deficient (not anemic) had poorer performances on skill tests than those with normal levels.
To fight wrinkles: broccoli
"A cup of broccoli has 100 percent of your vitamin C-crucial for production of collagen, which gives skin elasticity," says Tammy Lakatos Shames, R.D. It's also rich in beta-carotene, which the body converts to vitamin A. This vitamin assists in cell turnover, so old skin cells are replaced with fresh (read: younger-looking) ones.
To get healthy carbs: potatoes
Potatoes contain a fat-fighting compound called resistant starch that can help keep weight in check. One medium spud with the skin will run you just around 100 calories, and with more potassium than bananas, potatoes also help fight heart disease by keeping blood pressure low.
To up your intake of folate: spinach
This leafy green is high in vitamin K and also contains calcium and magnesium - a combo that may help slow the breakdown of bone that occurs as you get older - as well as folate, a B vitamin that helps prevent birth defects. And it packs just 7 calories per cup raw!
To stress less: dark chocolate
European researchers found that people who ate an ounce and a half of dark chocolate - about 200 calories worth-every day for two weeks produced less of the stress hormone cortisol and reported feeling less frazzled. Cortisol causes a temporary rise in blood pressure; consistently high levels up your risk for depression, obesity, heart disease and more.
To fight cancer: mushrooms
One study showed that women who ate just one third of an ounce of raw mushrooms a day (that's about one button mushroom) had a 64 percent reduction in breast cancer risk. Other research suggests that mushrooms reduce the effects of aromatase, a protein that helps produce estrogen - a major factor in some breast cancers.
To fight heart disease: sardines
These pungent little fish are good sources of omega-3 acids, which decrease inflammation that can lead to blocked arteries. They also prevent blood clots that can cause heart attacks and strokes, and keep blood vessels smooth and supple. Three ounces of sardines have about 1.3 grams of omega-3s (you need about 1 gram a day).
To help flatten your belly: avocados
Avocados are high in monounsaturated fat, which has been shown to help you drop weight, including from your troublesome middle. In one study, people who got the most monos (about 23 percent of their daily calories) had about 5 pounds less belly fat than those who ate a high-carb, lower-fat diet.
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To protect your eyes: bell peppers
Age-related macular degeneration (AMD) and cataracts are leading causes of vision loss, but foods rich in lutein, zeaxanthin, and vitamin C, like bell peppers, can keep eyes sharp. A cup of sliced red, yellow and orange peppers contains nearly twice your daily vitamin C, plus 116 micrograms (mcg) of lutein, and 562 mcg of zeaxanthin.
To boost energy: whole-grain pasta
Whole-grain pasta is loaded with B vitamins, which help your body convert food into energy. And unlike processed grain products that lack fiber, whole grains are more filling than their refined counterparts. In other words, you'll feel satisfied with fewer calories.
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