Vitamin A has several forms that are used for vital functions. Provitamin A, betacarotene, performs antioxidant functions that none of the other forms of vitamin A can achieve. In addition to its vital antioxidant functions, beta-carotene can be split apart into retinal and converted to all other forms

of preformed vitamin A.

Beta-carotene is one of the most powerful antioxidants in food. Antioxidants neutralize free radicals to reduce the risk of macular degeneration, cancer, heart disease, and stroke. Some of the beta-carotene in foods and supplements can be converted into the retinal form of vitamin A. About 10 percent of the carotenoids (beta-carotene is one of the carotenoids) in plant foods can be converted into retinal.

The remaining carotenoids may be used as antioxidants.

The other forms of vitamin A do not exhibit antioxidant activity. The forms of vitamin A found in meat (retinyl esters), dairy products, and eggs do not possess antioxidant activity. Vitamin A supplements made without beta-carotene or other sources of antioxidants also do not possess antioxidant activity. Many supplements are made with retinyl palmitate and retinyl acetate; these forms of vitamin A are not antioxidants.

Beta-carotene is plentiful in yellow and orange vegetables and fruit. Green vegetables also are rich in beta-carotene; the colorful pigments are masked by the green chlorophyll. Some of the other carotenoids that can be converted into retinal include alpha-carotene and beta- cryptoxanthin. Some carotenoids that cannot be converted into retinal are lycopene (from tomatoes) and lutein. All carotenoids have antioxidant activity.

To get the maximum health benefit you should eat antioxidant rich foods every single day. The best way of getting enough of all nutrients your body needs is to always eat a wide variety of healthy foods.

The way you prepare your foods also has a great impact on their antioxidants. Most foods lose some of their antioxidant power when you process them, except tomatoes. Tomato antioxidant capacity is enhanced when you cook them. But in general it is better to consume fresh foods instead of cooked or frozen ones, which is certainly easy with fruit.

Many foods contain antioxidant properties, but a few give you the most disease-fighting bang for your bite.

Some of the best antioxidant all-stars include: berries, walnuts, pomegranate juice and grape juice, sweet potatoes, unsweetened baking chocolate.

You need about 4 to 5 cups of fresh fruits and vegetables on a daily basis to offer the most protection for our systems.

By all means eat those salads on a daily basis, add walnuts, blueberries, strawberries, grapes of all colors, bananas, apple slices, dried cranberries, dried raisins, just to name few of the many ingredients to change and improve our diets with just eating a salad.

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