Why is getting plenty of vitamins through the foods you eat such a critical part of a healthy diet? The reason: Vitamins have been shown to aid in the prevention of heart disease, osteoporosis, macular degeneration, cancer, and a variety of other ailments. Since your body isn’t able to make most vitamins on its own (vitamins A, D, and K are exceptions), it’s important to eat a healthy, balanced diet. Here’s a primer on some of the most important vitamins you should be getting:

Vitamin A
Health benefits: Vitamin A is necessary to keep your eyes healthy, and it helps form bones and teeth, stimulates white blood cells to help build immunity, and regulates cell growth and division. The body makes some vitamin A in the intestine from beta-carotene and other carotenoids.
Make sure to eat… fortified dairy products, egg yolks, and dark-green, yellow, and orange vegetables containing beta-carotene (a precursor to vitamin A), such as broccoli, spinach, and on Phases 2 and 3, sweet potatoes, pumpkin, and carrots. Also on Phases 2 and 3, include fortified breakfast cereals, as well as fruits high in beta-carotene, such as cantaloupe and apricots.

Vitamin B (B6, B12, and folate)
Health benefits: B vitamins have been shown to aid in the prevention of heart disease, stroke, cancer, and other diseases. Vitamin B6 helps your cells make proteins. It also aids in manufacturing brain chemicals such as serotonin and in releasing stored forms of energy. Vitamin B12 is vital to cell development, especially the red blood cells. Folate (also called folacin and folic acid in its synthetic form) is used by the body to make blood cells, heal wounds, and protect against colorectal cancer.
Make sure to eat… grain products, including breakfast cereals and breads (Phases 2 and 3); eggs, trans-fat-free peanut butter, pork and other lean meats, chicken breast, and fish (all Phases); sardines, salmon, fortified soy products, and low-fat and fat-free dairy products (all Phases) for B6 and B12 vitamins. Some sources of folate are dark-green leafy vegetables, legumes, and brussels sprouts (all Phases), as well as wheat germ, whole grains, and sweet potatoes (Phases 2 and 3).

Vitamin C
Health benefits: This important vitamin can help prevent certain cancers, lower blood pressure, ensure proper functioning of the immune system, and build collagen, the connective tissue that stabilizes bone, muscle, and other tissues.
Make sure to eat… broccoli, brussels sprouts, spinach, red and green bell peppers (all Phases); fortified breakfast cereals, citrus fruits, and berries (Phases 2 and 3).

Vitamin D
Health benefits: Essential for building healthy bones, vitamin D may also strengthen the immune system and help prevent heart disease and some cancers. Technically a hormone, vitamin D is produced within the body when the skin is exposed to the UVB rays in sunlight. But many people don’t get enough sun to generate adequate vitamin D, so including it in your diet is important. If your doctor finds you have a vitamin D deficiency, he may recommend taking a supplement.
Make sure to eat… mushrooms, fortified dairy products, egg yolks, and fatty fish like salmon and light tuna (all Phases); fortified breakfast cereals (Phases 2 and 3).

Vitamin E
Health benefits: Vitamin E's main function is as an antioxidant, helping to protect tissues against free radicals, the unstable oxygen molecules that cause damage to cells. Vitamin E may help protect against cardiovascular disease, although studies are inconclusive. It may reduce the blood’s ability to clot, thus decreasing the risk of heart attacks. Vitamin E may also lower the risk of some types of cancer as well as arthritis, Parkinson’s disease, Alzheimer’s disease, and diabetes, although the evidence is preliminary for these conditions.
Make sure to eat… vegetable oils, sunflower seeds, egg yolks, dark-green leafy vegetables, nuts (all Phases); wheat germ, sweet potato, and whole grains (Phases 2 and 3).

Vitamin K
Health benefits: This vitamin is crucial for blood clotting and also plays a role in making a protein that is essential for bone formation. Most of the body’s needs for vitamin K are met by bacteria in the intestines that produce this vitamin, but about 20 percent comes from foods.
Make sure to eat… dark-green leafy vegetables, including kale, spinach, collard greens, and parsley, as well as vegetable oils, in particular soybean oil (all Phases).

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