Questions To Ask Before Taking Vitamin and Mineral Supplements



Questions To Ask Before Taking Vitamin and Mineral Supplements
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Are you considering taking vitamin or mineral supplements? Do you think you need them? Or that they "can't hurt" so you may as well take them? Here are some questions to ask before you decide to take them.


1. Do I really need them?

First and foremost, nutritional needs should be met by eating a variety of foods as outlined in the Dietary Guidelines for Americans. In some cases, vitamin/mineral supplements or fortified foods may be useful for providing nutrients that may otherwise be eaten in less than recommended amounts. If you are already eating the recommended amount of a nutrient, you may not get any further health benefit from taking a supplement. In some cases, supplements and fortified foods may actually cause you to exceed safe levels of intake of nutrients.

(Note that fortified foods are those to which one or more essential nutrients have been added to increase their nutritional value.)

The Dietary Guidelines for Americans makes these recommendations for certain groups of people:

  • People over age 50 should consume vitamin B12 in its crystalline form, that is, from fortified foods (like some fortified breakfast cereals) or as a supplement.

    (Note that older adults often have a reduced ability to absorb vitamin B12 from foods. However, crystalline vitamin B12, the type of vitamin B12 used in supplements and in fortified foods, is much more easily absorbed.)

  • Women of childbearing age who may become pregnant and adolescent females should eat foods that are a source of heme-iron (such as meats) and/or they should eat iron-rich plant foods (like cooked dry beans or spinach) or iron-fortified foods (like fortified cereals) along with a source of vitamin C.
  • Women of childbearing age who may become pregnant and those who are pregnant should consume adequate synthetic folic acid daily (from fortified foods or supplements) in addition to food forms of folate from a varied diet.
  • Older adults, people with dark skin, and people who get insufficient exposure to sunlight should consume extra vitamin D from vitamin D-fortified foods and/or supplements.

It is important to note that vitamin/mineral supplements are not a replacement for a healthful diet. Remember that in addition to vitamins and minerals, foods also contain hundreds of naturally occurring substances that can help protect your health.

Here are some questions that the Food and Drug Administration recommends asking yourself and discussing with your doctor when considering whether you should take a vitamin/mineral supplement:

  • Do you eat fewer than 2 meals per day?
  • Is your diet restricted? That is, do you not eat meat, or milk or milk products, or eat fewer than 5 servings of fruits and vegetables per day?
  • Do you eat alone most of the time?
  • Without wanting to, have you lost or gained more than 10 pounds in the last 6 months?
  • Do you take 3 or more prescription or over-the-counter medicines a day?
  • Do you have 3 or more drinks of alcohol a day?

2. Should I talk to my doctor about taking vitamin/mineral supplements?

Yes, you and your doctor should work together to determine if a vitamin/mineral supplement is right for you.

If you are already taking dietary supplements, you should inform your doctor. Research shows that many people do not let their doctors know that they are taking a dietary supplement or are considering taking one. You may think side effects happen only with prescription medicines, but some dietary supplements can cause side effects if taken with other medications or if certain health conditions exist. Even if you don't take medication or have a chronic health problem, the wrong dietary supplement or the wrong amount, can cause problems. So check with your doctor before taking a dietary supplement.

3. Where can I find scientifically sound information about vitamin/mineral supplements?

Your doctor is a good place to start. In addition, pharmacists and registered dietitians are helpful.

The NIH Office of Dietary Supplements has a series of Vitamin and Mineral Fact Sheets that provide scientifically-based overviews of a number of vitamins and minerals. They can provide a good basis for a discussion with your doctor about whether or not you should take a vitamin/mineral supplement.

MedlinePlus is another good source of information.

The Food and Drug Administration (FDA) has a variety of articles and consumer advisories to help consumers inform themselves about dietary supplements, including warnings and safety information, labeling, evaluation information, and FDA's role in regulating dietary supplements.

For those interested in looking directly at scientific studies, the PubMed Dietary Supplement Subset is a good database to search.

4. What should I do if I suspect I may be having a side-effect from a dietary supplement?

First, stop taking the supplement. Next tell your doctor or health care professional. The MedWatch Reporting Program also gives you information about how to report a problem to the Food and Drug Administration.

In summary, check with your doctor or a registered dietitian about which, if any, vitamin or mineral supplements might be right for you. And remember that while there are circumstances when it may be appropriate to take vitamin/mineral supplements, they are not a replacement for a healthful diet.

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