Vitamins C and E are popular candidates for people looking for antioxidant supplements. Dean Schneider expounds on the daily requirements for each, and whether these can easily be met with your diet.

For the last decade sales of vitamin C and E supplements have increased steadily as each study has confirmed their antioxidant properties and their abilities to lower the risk of several important diseases. Recently, vitamin sales have plummeted as some new studies suggest that supplemental vitamins do not lower risk, and/or are potentially dangerous. What should you do in the face of this turnaround? Here are a few tips:

Take the long view

It's not unusual for scientific studies on the same subject to have different conclusions. This may be related to the design of the study, the choice of population studied, the techniques employed, and the type of analysis. There's a large body of evidence that supplemental vitamins C and E can lower your risk of heart attacks, cancer and cataracts. A few studies that show no effects should not necessarily stop you from taking your antioxidant supplement.

Consider your risk factors

If you are 20 years old and have no risk factors for heart disease, you may want to wait for more convincing scientific evidence before starting vitamin supplements. However, if you're 50 and have risk factors for heart disease, such as being male, smoking, having a family history of heart disease, having high blood pressure, or being substantially overweight, you may not want to delay a possible life saving intervention.

Consider your age

Risk factors change with age. Having a raised cholesterol, being overweight, or having a family history of heart disease are much greater risk factors at age 40 than they are at age 80. By contrast, having low levels of antioxidants in your blood could be a greater risk factor as you age. This is confirmed by a recent study of 80-year-olds, where low blood levels of vitamin E were found to be a significant risk factor for heart attacks, while high cholesterol levels produced no increased risk ¹ .

Weigh the risks and rewards

Almost all prescription drugs have side effects and complications. However, doctors continue to prescribe them for specific conditions since their beneficial effects outweigh their harmful effects. In considering supplements, you need to assess your potential risks and rewards. The risks of taking modest doses of supplemental vitamin C and E (250 mg of vitamin C and 400 mg of vitamin E) are small, if any. There are few indications of adverse responses to these levels of vitamin supplements. The benefits could be immense if your risk of having heart disease, cancer, or cataracts is reduced.

How much vitamin C should I take a day?

Linus Pauling was an incredible scientist who won two Nobel Prizes. He also promoted vitamin C usage decades before others recognized its great antioxidant properties. He recommended megadoses of vitamin C, as much as 15,000 mg a day. I once had the audacity to tell Linus that these high doses of ascorbic acid (vitamin C), just like any acid, might cause some stomach problems. Of course I failed to convince him, a strong-minded scientist who had a strong stomach. However, today there are abundant studies that indicate that 250 mg a day of vitamin C provides substantial antioxidant protection. Furthermore, the human body can't metabolize more than 250 mg of vitamin C per day - any additional consumed vitamin C is excreted.

As I indicated in Part III of this series, the best way to get your vitamin C is though your diet. Here are a list of some foods and the amount of vitamin C they contain ² :

How much vitamin E should I take a day?

The clinical studies that displayed the beneficial effects of vitamin E employed doses of 100 International Units (IU) or 400 IU a day. In contrast to vitamin C, there is little data on how much vitamin E the body can utilize per day. 400 IU a day is probably better than 100 IU, since fat-soluble vitamins like vitamin E do not get into the blood stream as easily as the water-soluble vitamins.

It is almost impossible to get enough vitamin E in your diet. A brief look at the list of the foods which contain vitamin E (below) ² will demonstrate that even the most health conscious, compulsive nutritional expert will be hard pressed to get even the RDA of vitamin E (60 IU a day) through their diet. Of course, if you are willing to drink a few tablespoons of wheat germ oil or eat a couple of jars of sunflower seeds each day, you could prove me wrong.

Many of you take your supplemental vitamin E with your non-fat breakfast or before you go to bed at night. Since vitamin E is fat soluble, it is more effectively absorbed from your intestines when accompanied by some dietary fat. Therefore, you should take your supplemental vitamin E at lunch or at dinner, meals that usually contain more fat than breakfast.

Information provided in this article is for informational purposes and is not meant to substitute for the advice furnished by your own physician or other medical professional. This content should not be utilized for diagnosing or treating a health problem or disease, or prescribing any medication. Before taking any health product, you should read carefully all product packaging. If you have or suspect that you have a medical problem, promptly contact your health care provider. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease.

Links

• Click here to read all the articles in this "Oxidative Damage" series
• Vitamin C - A Major Part of '5 a Day'
• How Much Vitamin E is Really Enough?

Footnotes

1.

Vitamin E and lipid peroxide plasma levels predict the risk of cardiovascular events in a group of healthy very old people A. Mezzetti, G. Zuliani, F. Romano,  et al., J Am Geriatr Soc, 2001, vol. 49, pp. 533--537

2. The Wellness Nutrition Counter: by Sheldon Margen and the editors of the University of California at Berkeley Wellness Letter , Rebus Press, New York, 1997