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Do you need to take dietary supplements? The answer depends on your eating and lifestyle habits and some factors beyond your control, such as your age. Dietary supplements may be appropriate if:
- You don't eat well. If you eat less than five total servings of fruits and vegetables daily, it may be difficult to get all of the vitamins and minerals your body needs. Also, if you eat only one or two times a day, you may be limiting the number and variety of servings you eat from the various food groups.
- You're a vegetarian. If you're a vegetarian, you may not consume enough calcium, iron, zinc and vitamins B-12 and D. You can get these nutrients naturally from nonmeat sources, such as fortified soy products, green leafy vegetables, legumes, whole-grain products and nuts. If you aren't able to regularly consume these foods, dietary supplements may be necessary.
- You consume less than 1,200 calories a day. Low-calorie diets limit the types and amounts of foods you eat and, in turn, the types and amounts of nutrients you receive. Unless monitored by a doctor, a low-calorie diet isn't usually recommended.
- You have a medical condition that affects how your body absorbs, uses or excretes nutrients. If your diet has limited variety because of food allergies or intolerance to certain foods, such as dairy products, you may benefit from a dietary supplement. Also, if you have a disease of your liver, gallbladder, intestines or pancreas, or if you've had surgery on your digestive tract, you may not be able to digest and absorb nutrients properly. In such cases, your doctor may recommend that you take dietary supplements.
- You're a postmenopausal woman. After menopause, women experience a sudden drop in estrogen levels, which increases bone loss. To keep bones strong and to decrease bone loss, you need calcium as well as vitamin D — the vitamin essential for absorbing calcium. Women who don't obtain enough calcium and vitamin D through foods could benefit from taking a calcium supplement with vitamin D.
- You're a woman who has heavy menstrual bleeding. If you have heavy menstrual bleeding, you may need additional iron to replace the iron depleted by blood loss. Iron deficiency can lead to anemia, a condition in which blood is low in hemoglobin, the substance which carries oxygen to tissues.
- You're pregnant or trying to become pregnant. During this time, you need more of certain nutrients, especially calcium, folate and iron. Folate is needed very early in pregnancy to help protect your baby against neural tube birth defects, such as incomplete closure of the spine (spina bifida). Iron helps prevent fatigue by helping you make the red blood cells necessary to deliver oxygen to you and your baby. Your doctor can recommend a dietary supplement. It's important to start taking a supplement before becoming pregnant.
- You smoke. Tobacco decreases the absorption of many vitamins and minerals, including vitamin C, folate, magnesium and calcium. But dietary supplements won't make up for the major health risks caused by smoking. The safest option is to avoid all tobacco products.
- You drink excessively. Long-term excessive alcohol consumption can impair the digestion and absorption of several vitamins and minerals, including vitamin B-1, iron, zinc, magnesium and folate. In addition, you may substitute alcohol for food, resulting in a diet lacking in essential nutrients. Excessive drinking is defined as more than two drinks a day for men under age 65 and more than one drink a day for men over 65 and women. Taking dietary supplements, however, won't make up for the major health risks caused by excessive alcohol consumption.
If you're generally healthy and eat a wide variety of foods, including fruits, vegetables, whole grains, legumes and lean meats, you don't likely need dietary supplements.
But if you seek assurance that you're getting all the vitamins and minerals you need and you don't mind the added expense and daily routine of taking a pill, taking a standard vitamin and mineral supplement with about 100 percent of the Daily Value (DV) for the various vitamins and minerals is generally fine. It's always a good idea, however, to talk with your doctor, as he or she knows your history and specific situation best.