Vitamin intake should be closely monitored

Q. Are vitamins worth taking?

It’s very important to talk with your doctor before you take any vitamin and mineral pills, especially if you take prescription medicines, have any health problems or are elderly. Taking too much of a vitamin or mineral can cause problems with some medical tests or interfere with drugs you’re taking.

Vitamins and minerals are “micronutrients” your body needs in small, but steady amounts. Your body can’t make most micronutrients, so you must get them elsewhere.

Vitamins are natural substances found in plants and animals. There are two types of vitamins: water-soluble and fat-soluble.

Water-soluble vitamins are easily absorbed by your body. Unlike fat-soluble vitamins, they don’t have to be absorbed using bile acids (fluids used to digest fats). Your body doesn’t store large amounts of water-soluble vitamins. The water-soluble vitamins you don’t need are removed by your kidneys and come out in your urine

Your body has to use bile acids to absorb fat-soluble vitamins. Once these vitamins are absorbed, your body stores them in body fat. When you need them, your body takes them out of storage to be used.

Here are some water-soluble vitamins: Vitamin C, biotin and the seven B vitamins - thiamin (B-1), riboflavin (B-2), niacin (B-3), pantothenic acid (B-5), pyridoxine (B-6), folic acid (B-9) and cobalamin (B-12). Here are some fat-soluble vitamins: A, D, E or K.

Minerals come from the earth or from water. Plants and animals absorb them to get nutrients. The “major minerals” are calcium, phosphorus, magnesium, sodium, potassium, sulfur and chloride. They are considered major minerals because adults need them in large amounts.

The “trace minerals” are chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium and zinc. Your body needs them in smaller amounts.

It would be hard to “overdose” on vitamins or minerals that you get from the foods you eat. But if you take supplements, you can easily take too much. This is even more of a risk if you take fat-soluble vitamins.

Whole foods are your best sources of vitamins and minerals. They offer three main benefits over supplements;

1. They contain a variety of the micronutrients your body needs. An orange, for example, provides vitamin C but also beta carotene, calcium and other nutrients. A vitamin C supplement lacks these other micronutrients.

2. They provide dietary fiber, which is important for digestion and can help prevent certain diseases such as cancer, diabetes and heart disease. Adequate fiber intake can also help prevent constipation.

3. They contain other substances such as antioxidants which slow down the natural process that leads to cell and tissue damage. If you depend on supplements rather than eating a variety of whole foods, you miss the potential benefits of these substances.

For some people, including those on restrictive diets, multivitamin-mineral supplements can provide vitamins and minerals that their diets often don’t. Older people and pregnant women have altered nutrient needs and may also benefit from a supplement.