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Do you need a vitamin supplement?
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The bottom line


Where do you fall short?
Where do you fall short?

The most common deficiencies in women tend to be in calcium, vitamin D, folate, iron and magnesium. Here’s how much you should be getting daily and the best food sources to get them from:

  • CALCIUM: Recommended dietary allowance (RDA) is 1,000 milligrams (mg). Good food sources include fortified cereals, milk, cheese, yogurt and fortified orange juice.
  • FOLATE: RDA is 400 micrograms (mcg) if you’re thinking of having a baby, 600 mcg if you’re already pregnant and 500 mcg if you’re lactating. Good food sources include cooked dry beans and peas, oranges and orange juice, spinach and mustard greens.
  • IRON: RDA is 18 mg. Good food sources include lean meats, spinach, clams, shrimp and oysters.
  • VITAMIN D: RDA is 200 international units (IU). Good food sources include cod liver oil, salmon, mackerel, tuna, milk and whole eggs. Sunlight also helps your body make vitamin D.
  • MAGNESIUM: RDA is 320 mg. Good food sources include halibut, cashews, almonds, peanuts, kidney beans. pinto beans and spinach.

Are you confused about the large number of vitamin and mineral supplements on store shelves and wonder whether you should be taking one—or more?

If your diet is filled with fruits, vegetables, whole grains, legumes and lean meats, you probably don’t need a supplement. And supplements can’t duplicate all the nutrients found in food sources.

If you suspect you may have a deficiency, talk with your healthcare provider. Some supplements can interfere with health conditions and medications. What’s more, taking too much of some vitamins can be toxic or cause side effects.

You may be prone to vitamin and mineral deficiencies if you:

  • Are a vegetarian. Meat supplies iron and vitamin B12, so if you don’t eat it, you may be lacking these nutrients. You may also come up short on calcium, zinc and vitamin D.
  • Bleed heavily during menstrual periods. Losing blood results in iron deficiency and anemia, which can lead to fatigue, irritability, dizziness and a feeling of being cold.
  • Are pregnant or trying to become pregnant. Your body needs more calcium, folate and iron during this time. Folate helps protect against birth defects.
  • Are pregnant or trying to become pregnant. Your body needs more calcium, folate and iron during this time. Folate helps protect against birth defects.
  • Smoke. Tobacco hinders folate, magnesium and calcium absorption. However, supplements won’t make up for the health risks caused by smoking.
  • Are a heavy alcohol drinker. Long-time drinking can hurt digestion and absorption of iron, zinc, magnesium and folate. Supplements can’t undo a heavy drinker’s health risks.
  • Eat less than 1,200 calories a day. If you’re dieting or skipping meals, you may not be getting the nutrients you need. But in general, a 1,200-calorie-a-day diet isn’t a wise health habit anyway.
  • Have a medical condition, such as liver, gallbladder or intestinal disease. These conditions may affect how your body absorbs nutrients.
  • Have an allergy or intolerance to certain foods such as dairy. If, for example, you’re lactose intolerant and can’t get enough calcium from food, a dietary supplement may help.
  • Are postmenopausal or have had a total hysterectomy. You likely need extra calcium and vitamin D to protect against bone loss.

The bottom line

Researchers continue to study whether supplements can prevent disease. In the meantime, your healthcare provider or a registered dietician can help you decide what’s right for you.