The vitamin supplements you take regularly can either support or harm your health. Dietary supplements that supply essential vitamins and minerals come in many forms, from liquids to tablets and single to multiple nutrient dosages. Some are more appropriate for certain health conditions. Other are tailored to general nutritional needs and individual eating habits. Before choosing between single vitamins and multivitamins, take many of your health and lifestyle variables into account.
Healthy supplementation begins with regular dosing. Select a vitamin product that will be convenient or easy to remember to take. Unless otherwise specified by the manufacturer, linking once- or twice-daily dosing with meals will help you absorb nutrients well and avoid stomach problems and inadvertent underdosing and overdosing. In addition to liquid vitamin drops, powders and various forms of tablets, fortified foods represent further dosing methods. Fortified orange juice and cereal, for instance, are convenient sources of single and multiple supplemental vitamins.
Meeting Daily Nutritional Needs
According to the National Institutes of Health Office of Dietary Supplements, about one-third of all Americans take a daily multivitamin or multivitamin/mineral supplement. Multivitamins help you achieve the recommended daily allowances of essentials vitamins consistently in one or two convenient tablets. On a doctor's advice, you might consider taking multivitamins if you are vegan, vegetarian, pregnant or breast-feeding. Multiple-vitamin supplementation is especially valuable to people whose diets aren't sufficiently varied or who have medical conditions that make it hard to eat enough or to fully absorb nutrients. Multivitamin effectiveness in preventing chronic illness in all population groups has not been established conclusively.
Single vitamin or mineral supplements are better suited to specific nutrient deficiencies or in support or prevention of certain diseases. Their use is encouraged by the National Institutes of Health for special population groups. Calcium and vitamin D protect bone health in postmenopausal women and other osteoporosis risk groups. Women who are or might become pregnant can prevent anemia with an iron supplement and birth defects with folic acid, or vitamin B-9. Adults older than age 50 can benefit from superior absorption of vitamin B-12 with a crystalline supplement. Discuss any vitamin supplements you wish to take with your doctor.
All types of vitamins may carry mild to dangerous side effects if used incorrectly. Purposefully taking too much of single vitamin or combining sources from multivitamins, single vitamins, fortified foods and your usual diet can produce toxic overdoses. Your risk is greatest regarding the fat-soluble vitamins A, D and E, which can build up in the body and cause serious health effects, including liver, kidney and brain damage. Your doctor's advice about multivitamins can help you avoid medication interactions.
- American Journal of Clinical Nutrition: Carotene-rich Plant Foods Ingested With Minimal Dietary Fat Enhance the Total-Body Vitamin A Pool Size in Filipino Schoolchildren
- U.S. Food and Drug Administration: Fortify Your Knowledge About Vitamins
- Office of Dietary Supplements: Multivitamin/Mineral Supplements
- MedlinePlus: Multivitamins
- National Institutes of Health: NIH State-of-the-Science Conference Statement on Multivitamin/Mineral Supplements and Chronic Disease Prevention
- Institute of Medicine of the National Academies: Dietary Reference Intakes, Vitamins