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Beware Overusing Dietary Supplements

Americans are consuming dietary supplements in record numbers. It's estimated that, last year alone, 192 million of us took supplements, and spent $23 billion on them.

But -- are they always safe? Or are we over-doing it, getting too much of what might otherwise be a good thing?

On The Early Show Wednesday, registered dietitian Keri Glassman stressed that supplements are meant to do just that -- supplement your diet. But, she added, we should be getting most of our nutrients from food.

However, many people fall short on certain nutrients, such as calcium, vitamin E, vitamin D, and essential fatty acids. And certain groups of people may need supplements (the elderly, vegetarians, pregnant women, etc).

There is absolutely a time and place for supplements, Glassman says. But she advises people to use them as "insurance" to supplement a healthy diet.

And they can be harmful in LARGE DOSES, Glassman points out -- more isn't always better. And, when they INTERACT with each other and/or medications, problems could result.

Water-Soluble Vitamins

The kidneys remove what the body doesn't need. But, overdoing some of them can still lead to problems:

  • B vitamins: upset stomach, flushing, nerve damage
  • Folic acid: another B vitamin, this can hide signs of B12 deficiency, a condition that can cause nerve damage.
  • Vitamin C: upset stomach, increased iron absorption

    Fat-Soluble Vitamins

    They're stored in the body. They include A, D, E and K. Possible problems include:

  • Vitamin A: nauseau, vomiting, dizziness, blurred vision, clumsiness, birth defects
  • Vitamin D: nauseau, vomiting, constipation, poor appetite, confusion, heart arrythmias, deposits of calcium in soft tissues
  • Vitamin E: may increase bleeding and prevent clotting
  • Vitamin K

    Something to remember: there are guidelines for the amounts you should take. You never want to exceed those amounts!


  • Regular Green Tea: contains caffeine; be aware of any medications that interact with caffeine. Also, green tea may contain vitamin K and can limit the effectiveness of blood thinners.
  • Gingko biloba: taken to improve memory; may increase bleeding and should be stopped before surgery or if at risk for bleeding
  • St Johns Wort

    What can you do?

  • Do your research as a consumer
  • Always discuss supplements you're taking or may take with your doctor
  • Take supplements as a supplement to your diet and NOT as a quick-fix or cure-all
  • Watch out for any odd side effects
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