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Missing Nutrients in Your Food

Even the most conscientious eaters may have dietary deficiencies.


You've probably heard all about the health benefits of fiber over the years. But given all the emphasis on bowels and regularity, you might assume that you won't have to worry about fiber intake until after retirement.

"People think that fiber is just for old people," says Kaiser. "But it's really important at every age for promoting a healthy intestinal tract and guarding against diseases."

So what does fiber do? In addition to keeping your bowels working well, it reduces the risk of other intestinal problems. Good fiber intake may also help protect against heart disease, type 2 diabetes, and some forms of cancer. Since fiber is so filling and low on calories, it's often key in many successful weight loss programs.

The amount of fiber you need depends on your age and your sex.

  • Women, age 19-50: 25 grams/day
  • Women, age 51 and older: 21 grams/day
  • Men, age 19-50: 38 grams/day
  • Men, age 51 and older: 30 grams/day

Some good sources of this nutrient in food include:

  • 100% bran cereal (1/2 cup): 8.8 grams
  • Cooked black beans (1/2 cup): 7.7 grams
  • Baked sweet potato, with peel: 4.8 grams
  • Small pear: 4.4 grams
  • Whole-wheat English muffin: 4.4 grams



Magnesium is involved in all sorts of bodily processes. It strengthens bones and keeps the immune system up to snuff. Magnesium also plays a key role in the function of your heart, muscles, and nerves.

The recommended daily allowance of magnesium is:

  • Women, age 19-30: 310 milligrams/day
  • Women, age 31 and older: 320 milligrams/day
  • Men, age 19-30: 400 milligrams/day
  • Men, age 31 and older: 420 milligrams/day

Good sources of this nutrient in food are:

  • Brazil nuts (1 ounce): 107 milligrams
  • 100% bran cereal (1 ounce): 103 milligrams
  • Cooked halibut (3 ounces): 91 milligrams
  • Almonds (1 ounce): 78 milligrams

Vitamin A

Vitamin A is crucial for a lot of reasons. It's good for vision -- that's why your mother always told you to eat your carrots. It's also important for immunity and tissue growth.

How much do you need?

  • Adult men: 900 micrograms/day
  • Adult women: 700 micrograms/day

However, there are actually two types of vitamin A: retinol and carotenoids. The latter are the ones that are missing from too many American diets. There's no official daily recommended amount of carotenoids that you need. But you should try to get some of this nutrient in your food every day.

Foods that have carotenoids include:

  • Baked sweet potato, with skin: 1,096 micrograms
  • Cooked fresh carrots (1/2 cup): 671 micrograms
  • Cooked spinach (1/2 cup): 573 micrograms
  • Cooked winter squash (1/2 cup): 260 micrograms

Vitamin A is also in many fortified cereals and oatmeal.

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Need some quick, fresh ideas? Ever wonder what's behind the latest food headlines? Check in with Elaine Magee, RD, MPH.

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