Nearly one-third of Americans take vitamin supplements that some studies have shown to have cancer-fighting properties, including vitamins E and C.
But two new studies suggest these supplements have little effect on healthy adults. So are you wasting you money?
CBS News health contributor and American Red Cross president Dr. Bernadine Healy spoke with The Saturday Early Show about significance of these new findings.
Previous studies have suggested that vitamin E might help protect blood vessels, brain cells, and other body parts from free radicals. These are normal byproducts of oxidation reactions in metabolism which play a role in everything from heart disease to Alzheimer's, Healy explains.
This particular new study from researchers at the University of Pennsylvania focused on vitamin E supplements and their effect on antioxidant damage to fat molecules. They took 30 healthy people, ages 18 to 60, and gave them vitamin E supplements in varying doses for eight weeks.
Putting The 'E' in Your Eats
Researchers found that, in the short term at least, no matter the dose, vitamin E supplements had no effect on antioxidant damage to lipids or fat molecules. However, vitamin E might still help prevent free radical damage of other important molecules such as proteins and DNA. More research is needed to determine that.
So is it a waste of money to take vitamin E supplements? If you are healthy and eat a well-balanced diet, most likely you don't need vitamin E supplements, Healy says. However, some heart specialists think they are still worth taking, especially for people who already have cardiovascular disease. Vitamin E is believed to slow the oxidation of low-density liporotein (LDL or "bad") cholesterol, which plays an important role in the disease process that leads to heart attacks and strokes. However, for healthy people, they are likely to get the full benefit of vitamin E from their diets through foods.
The recommended daily amount of vitamin E for men is 10 milligrams; for women it's 8 milligrams. It's extremely rare for people not to get enough vitamin E. You really need to check with your doctor to see if you need to take vitamin E supplements, Healy says. These supplements should be avoided by pregnant women and women who are breast-feeding. You also need to be aware of certain medications that might interact with vitamin E. Also, high doses for long periods of time can cause bleeding problems.
Good sources of vitamin E include milk, leafy vegetables, vegetable oils, whole-grain cereals, and eggs.
The Lowdown on Vitamin C
A lot of people swear that taking megadoses of vitamin C supplements can ward off everything from colds to cancerAre vitamin C supplements effective? ©MMII CBS Worldwide Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed
Healy says that vitamin C also has antioxidant properties that promote healthy blood vessels, collagen and other building blocks of the body. A new British study found that vitamin C obtained through fruits and vegetables may help people live longer.
Once again, it's the vitamin from food rather than supplements that is beneficial, she says. Researchers compared blood levels of vitamin C and death rates in early 20,000 men and women. They found that people with the most vitamin C in their blood reduced their risk of dying from chronic disorders like cardiovascular and heart disease. Each increase of 2 ounces of fruits and vegetables a day was linked to a 20% drop in the risk of death.
The government recommends 90 milligrams of vitamin C a day for men; 75 milligrams a day for women. It would be ideal for everyone to eat five servings of fruits and vegetables a day, but that's pretty difficult to do, Healy acknowledges. The study found tat once you get below three to four servings a day of fruits and vegetables, the risk starts to go up rapidly.
Some good sources of vitamin C are oranges, grapefruit, apples, bananas, and green vegetables.
People should be getting their vitamins through their foods and not supplements, Healy says. Vitamin supplements will not take the place of a good diet and will not provide energy.
Be conscious of what you eat and put some effort into choosing a balanced and varied diet to get all of those good vitamins, she says.
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