Vitamins and minerals help give you energy, fight disease and increase athletic performance. But it's common for many American women to skimp on these health boosters and become dangerously deficient. Before rushing to the supplement aisle, recognize that the best health-promoting vitamins and minerals aren't found in pills.
"Food first," says Kerry Neville, M.S., R.D., spokesperson for the American Dietetic Association. Neville recommends vitamin and mineral supplements only to augment an already balanced diet, or if you avoid whole food groups because of allergies, intolerances or other reasons, such as being a vegetarian. There are thousands of phytonutrients in food, she says, but only a few hundred have been researched. No pill can duplicate the chemical reactions of your breakfast, lunch and dinner.
So head to the grocery store to get your hardworking body most of what it needs to carry you through the day and fend off illness. Here are some star nutrients that may need some pumping up in your diet.
Vitamin A is a group of compounds--beta carotene and retinol among them--important in immune function, vision, bone growth and cell division. Fruits and vegetables provide vitamin A in the form of beta carotene and other carotenoids. Vitamin A from animal sources comes as retinol.
You'll have no problem getting the RDA of vitamin A (2,310 International Units or IUs) if you eat five to nine servings of colorful fruits and vegetables daily. The best sources of beta carotene: orange fruits and vegetables such as carrots, sweet potatoes, cantaloupe and mangoes; green leafy vegetables such as spinach and kale; red fruits and vegetables like watermelon and tomatoes. For retinol, consume chicken liver, whole milk, fortified nonfat milk and other dairy products or eggs.
Be careful when choosing a vitamin A supplement. Sometimes supplements can be harmful, says Edgar Miller, Ph.D., M.D., professor of Medicine and Epidemiology at Johns Hopkins Medical University. Consider what scientists learned about beta carotene supplements in the '80s and '90s. Researchers observed that people who ate ample fruits and vegetables rich in vitamin A had lower rates of lung cancer. However, they also found that male smokers receiving beta carotene supplements were more likely to develop lung cancer. Taking large doses of antioxidant supplements may interfere with the body's own defense mechanisms, suggests Miller.
Supplemental vitamin A, found in multivitamins, is often made of retinol (often seen as vitamin A palmitate or acetate), beta carotene or a combination of both. Excess retinol is associated with birth defects, liver disease, osteoporosis and hip fracture. (Don't take a multivitamin that lists a Daily Value (DV) of more than 100 percent for retinol.) Similarly, the IOM does not recommend beta carotene supplements for the general population. So, aim for a multivitamin with both sources listed, and if it simply lists vitamin A, leave it alone since you don't know the source.
This B vitamin is needed for DNA synthesis and cell division. During growth periods such as pregnancy and infancy, folate requirements increase to keep up with rapid cell division. Since the body absorbs folic acid, the synthetic form of the vitamin, more easily than the food form, the FDA requires all foods designated "enriched" to have added folic acid, says Lynn Bailey, professor of nutrition at the University of Florida. This ensures that women of reproductive age consume enough of the vitamin to reduce the risk of neural tube defects such as spina bifida and other birth defects.
Folate is required for the synthesis of blood and muscle cells, so a deficiency means less oxygen-carrying ability and a decrease in your physical performance, says Bailey. "Taking extra folic acid, however, does not enhance your ability to perform athletic activities." Some studies suggest that folate is important in the prevention of heart disease, cancers and Alzheimer's disease.
Aim for 400 micrograms (mcg) per day unless you're pregnant or planning to become pregnant soon. Then you'll need 600 mcg daily. Boost your folate levels with fortified breakfast cereals, fortified breads, dried beans and peas, green leafy vegetables and oranges.
Every food that comes from animals contains this vitamin, which is necessary to make DNA and maintain healthy nerve and red blood cells. National health surveys show that most Americans consume adequate amounts of vitamin B12. However, strict vegetarians will need to supplement, as will older people lacking the stomach acid necessary to extract the vitamin from food. If you are older than 50 experts advise that you get 2.4 mcg from a supplement or fortified food such as breakfast cereal.
It often takes years to deplete the body's normal reserves, so deficiency symptoms appear slowly. They include anemia, fatigue, depression and nerve damage such as tingling in the hands and feet. If the deficiency persists, the nerve damage will be permanent. To avoid developing a deficiency, eat fortified breakfast cereals, beef, fish, poultry, pork, dairy and eggs.
Vitamin C acts as an antioxidant, aids the immune system and is necessary for the synthesis of collagen, the major protein of bone, teeth, skin, cartilage and tendons.
Reports of large doses of vitamin C preventing the common cold are controversial. The general consensus is that although vitamin C doesn't prevent a cold, it can reduce the severity of symptoms.
Eating plenty of fruits and vegetables will assure you consume several times the RDA. (The RDA for women is 75 mg, the amount in about 5 ounces of orange juice or just over a cup of cantaloupe.) Some experts recommend amounts several times the RDA, believing it helps prevent chronic diseases. Sources high in vitamin C: broccoli, sweet peppers, tomato products, citrus fruit, cantaloupe, guava, kiwis and strawberries.