It’s no secret that eating plenty of fruits and vegetables is an important part of a healthy diet. Rich in fiber and essential vitamins and minerals, fruits and vegetables contain many other components that promote good health. One such component—carotenoids—gives some fruits and vegetables a particularly healthy punch by reducing the risk for chronic diseases like cancer, heart disease and eye degeneration.
Carotenoids are naturally occurring pigments that give many red, yellow, orange and dark green fruits and vegetables their vivid color. Brightly colored foods like carrots, sweet potatoes, spinach and peppers contain high levels of carotenoids. While scientists have discovered hundreds of carotenoids, you may be familiar with some of the common ones: beta-carotene, alpha-carotene, lycopene and lutein.
Far more than nature’s paint palette, carotenoids are a main dietary source of vitamin A because the body converts some carotenoids (beta-carotene, alpha-carotene and beta-cryptoxanthin) to vitamin A, necessary for proper vision, bone growth, immune system function, reproduction and cell division. Carotenoids function as powerful antioxidants, protecting your body against tissue damage that occurs with normal metabolism. Because this damage is associated with increased cancer risk, diets high in antioxidant carotenoids seem to lower that risk.
It’s best to get your carotenoids from eating fruits and vegetables rich in these nutrients because some studies of carotenoids in supplement form have produced mixed results. And two studies found beta-carotene supplements were associated with a higher risk of lung cancer among smokers and former asbestos workers. While megadosing with vitamin A supplements can result in toxicity, the worst that may happen with eating large quantities of carotenoid-rich foods would be temporary and harmless yellow or orange skin discoloration.
Government health agencies and the American Cancer Society agree the best way to get your carotenoids is to include at least five servings (nine is better) of fruits and vegetables in your daily meals and snacks. (See “A rainbow of choices.”) A good rule of thumb: The more vivid the color, the greater the carotenoids.
Preparing, chopping, pureeing and cooking these foods may enhance how well your body can absorb their micronutrients. For example, the lycopene in tomato products is increased when the foods are processed at high temperatures. Your body can absorb the lycopene from canned, pasteurized tomato juice better than it can when you eat a fresh tomato. Lightly steaming carrots and spinach works, too. However, prolonged heating or overcooking usually decreases the nutrients in vegetables.
Because these micronutrients are better absorbed by the body when eaten with some fat, you should enjoy a bit of olive oil drizzled on your spinach salad. On the other hand, taking cholesterol-lowering drugs, mineral oil or medications to treat obesity may inhibit absorption of carotenoids. Talk to your doctor about whether he or she thinks your carotenoid intake is sufficient.