The body needs vitamins and minerals to grow, develop, and stay healthy. Also called “micronutrients,” vitamins and minerals are needed only in small amounts, unlike “macronutrients” (carbohydrate, protein, and fat), which supply the body with energy. Ideally, following a healthy diet would provide you with all of the micronutrients you need, but sometimes even a healthy diet leaves gaps, and if you don’t consume the recommended amounts of fruits, vegetables, and whole grains, for example, you may be shortchanging yourself on certain important vitamins and minerals. But vitamin supplements aren’t necessarily a quick fix — and in some situations, they can do more harm than good. What can vitamin supplements do for you? Read on to find out. (You’ll find answers later in this article.)
1. Which of the following groups of people may benefit most from taking a multivitamin or mineral supplement? (More than one answer may be correct.)
A. Older adults.
B. Pregnant women.
C. People following a vegan diet.
D. People dieting to lose weight.
2. Taking a multivitamin or mineral supplement can help you prevent heart disease, stroke, and cancer.
3. Which of the following nutrients are commonly underconsumed?
B. Vitamin D.
D. Vitamin K.
4. If you take metformin to help manage your diabetes, you may be at risk for a deficiency of which of the following nutrients?
B. Vitamin C.
D. Vitamin B12.
5. Men and postmenopausal women should choose a multivitamin or mineral supplement that contains no more than 10 milligrams of which of the following nutrients?
A. Vitamin C.
6. Taking vitamin supplements will give you more energy.
7. The best vitamin supplements contain extra ingredients, such as herbs, and usually cost a lot of money.
1. A, B, C, and D. Not everyone needs to take vitamin supplements, but certain populations may benefit more than most. For example, pregnant women need to make sure they get enough iron and folic acid. Vegans (folks who don’t eat meat, poultry, seafood, eggs, or dairy) should probably take a vitamin B12 supplement, since B12 is mostly found in foods of animal origin. And older adults who may have difficulty fitting in the components of a healthy diet due to illness, poor appetite, or financial struggles may benefit from taking a multivitamin to help ensure that they’re meeting their nutrient requirements. Another group of people who should probably take a multivitamin are people who are following weight-reduction diets, especially those that are low in carbohydrate.
2. FALSE. There has been a lot of confusing — and conflicting — information about the role that vitamins may (or may not) play in preventing diseases, such as heart disease, stroke, and cancer. However, the Physicians’ Health Study, which followed almost 15,000 male physicians for 13 years, found no evidence that taking a multivitamin prevented heart attack, heart disease, or stroke. The same held true for the women in an even larger study, the Women’s Health Initiative. Also, neither study showed any benefit of taking a multivitamin on cancer prevention. Some health-care professionals believe that it’s a good idea to take a multivitamin or mineral supplement for “insurance” purposes, and people with certain types of chronic diseases may benefit from taking one; however, there’s no good evidence yet that doing so will actually prevent disease.
3. B. Vitamin D, a nutrient needed for bone health, has gotten a lot of press over the past few years, because anywhere from 40% to 85% of the American population is believed to be deficient. Also known as the “sunshine vitamin,” vitamin D is a hormone that the body makes from sunlight. It’s hard to get enough sunlight during the winter months, unless you live in the southern part of the country. It’s also hard to get enough vitamin D from foods, as only a small handful contain this vitamin, including fatty fish (and fortified foods, such as milk). The Institute of Medicine recommends that adults aim for 600 IU (international units) of vitamin D each day; people older than 70 should get 800 IU. Most multivitamins contain at least 400 IU. Talk with your health-care provider about whether you should take a vitamin D supplement to help meet your daily needs.
4. D. Vitamin B12 is needed for a healthy nervous system and blood cells. People who take metformin, the most commonly used diabetes medicine, are at risk for vitamin B12 deficiency. That’s because metformin may interfere with B12 absorption and, if not treated, lead to a deficiency. B12 deficiency can cause weakness, fatigue, constipation, loss of appetite, weight loss, and a type of anemia called megaloblastic anemia. A lack of sufficient B12 can also damage the nervous system and cause peripheral neuropathy (nerve damage in the feet, legs, and hands). If you take metformin, talk to your health-care provider about regularly getting your level of vitamin B12 checked; if it’s too low, you will likely need to take a B12 supplement.
5. C. Iron is an essential mineral that carries oxygen from the lungs throughout the body and helps the body’s cells work properly. Children, adolescents, women of childbearing age, and pregnant women are at a higher risk of developing an iron deficiency, which is the leading cause of anemia. People who are on dialysis or who have gastrointestinal disorders, such as Crohn disease, are also at risk. However, in the absence of these conditions, women who have gone through menopause and men are at low risk for iron deficiency. They are also at a higher risk for iron overload, a condition in which excess iron is stored in the body’s organs (including the heart and liver), leading to damage. These two groups of people only need about 8 mg to 10 mg of iron each day, compared to 18 mg for premenopausal women. Because of this, it’s important that men and postmenopausal women not take iron supplements (unless advised to do so by a health-care provider) and, if taking a multivitamin/mineral supplement, to choose one with no more than 10 mg of iron.
6. FALSE. Many people believe that if they’re feeling run down or tired, they should start taking vitamins. However, unlike carbohydrate, protein, and fat, vitamins and minerals do not provide the body with calories, which means they are not a source of energy. Certain vitamins and minerals do help the body process food to be used for energy, and if you’re deficient in any vitamin (especially any of the B vitamins), it’s possible that you won’t feel too well. But, with the exception of vitamin B12, deficiencies in these types of micronutrients aren’t that common. And don’t fall into the trap of thinking that if taking some is good, taking more — of any vitamin — is better. Some vitamins, like some of the B vitamins and vitamin C, will simply wash out in your urine if you take too much; others can be harmful. Always pay attention to the dosing instructions on the label, and talk to your doctor before starting to take any vitamin supplement.