Vitamins are micronutrients, or substances that the body uses in small amounts, as compared to macronutrients, which are the proteins, fats, and carbohydrates that make up all food. Vitamins are present in food, but adequate quantities of vitamins may be reduced when food is overcooked, processed, or improperly stored. For instance, processing whole wheat grain into white flour reduces the contents of vitamins B and E, fiber, and minerals, including zinc and iron. The body requires vitamins to support its basic biochemical functions, and deficiencies over time can lead to illness and disease.

Vitamin A can become toxic when taken in large amounts (over 100,000 International Units) on a daily basis over time, as can vitamin D. Substituting beta-carotene for vitamin A can alleviate this risk. Very large doses of minerals taken over long periods may have toxic effects in the body. Dosages far exceeding RDA's of vitamins are not recommended, nor are large doses of other supplements.
Folate or vitamin B9 (also known as folic acid when used in fortified foods or taken as a supplement) is another nutrient that many women don’t get enough of in their diets. Folate can greatly reduce the chance of neurological birth defects when taken before conception and during the first few weeks of pregnancy. Folate can also lower a woman’s risk for heart disease and certain types of cancer, so even if you’re not planning on getting pregnant (and many pregnancies are unplanned), it’s an essential nutrient for every woman of childbearing age. In later life, folate can help your body manufacture estrogen during menopause.
When women reach childbearing age, they need to eat enough folate (or folic acid) to help decrease the risk of birth defects. The requirement for women who are not pregnant is 400 micrograms (mcg) per day. Including adequate amounts of foods that naturally contain folate, such as citrus fruits, leafy greens, beans and peas will help increase your intake of this B vitamin. There also are many foods that are fortified with folic acid, such as breakfast cereals, some rices and breads.  Eating a variety of foods is recommended to help meet nutrient needs, but a dietary supplement with folic acid also may be necessary. This is especially true for women who are pregnant or breast-feeding, since their daily need for folate is higher, 600 mcg and 500 mcg per day, respectively. Be sure to check with your physician or a registered dietitian nutritionist before taking any supplements., .
In addition to diet, exercise and other lifestyle factors can also play an important role in bone health. Smoking and drinking too much alcohol can increase your chances of developing osteoporosis, while weight-bearing exercise (such as walking, dancing, yoga, or lifting weights) can lower your risk. Strength or resistance training—using machines, free weights, elastic bands, or your own body weight—can be especially effective in helping to prevent loss of bone mass as you age.