Expert Nutrition

Vitamin E

(Tocopherol)

Vitamin E is a powerful antioxidant that helps protect the fatty membranes of cells from oxidative damage. Vitamin E also helps to maintain healthy red blood cells and muscle tissue, protect the lungs from pollutants and regulate the synthesis of Vitamin C and DNA.

There is accumulative evidence that vitamin E also plays an important role in reducing the risk and slowing the progression of heart disease. The mechanism behind this reduction is believed to be through the antioxidant effect of vitamin E on LDL (bad) cholesterol which prevents it from oxidising. Having high LDL cholesterol is a risk factor for heart disease but what is more concerning is if that LDL becomes oxidised. Oxidised LDL cholesterol is the really nasty stuff, as it is oxidised LDL that leads to atherosclerosis (hardening of the arteries).

Studies that have reviewed higher intakes of vitamin E have shown positive health outcomes through a reduction of cardiovascular risk, diabetes complications, some cancers and cataracts. Although these results appear promising further research is required before any strong conclusions can be made.

Although vitamin E is a fat soluble vitamin it is not believed to accumulate to toxic levels within the body that would negatively impact on our health. This is largely due to the fact that excess levels of vitamin E are normally excreted in stools. Many nutritional supplement companies would argue that given there is growing evidence that supplementation of vitamin E may have a protective effect against some degenerative diseases and that the risk of it accumulating within the body to toxicity is minimal, then there is good reason to consider vitamin E supplementation. For more information about the pros and cons of taking nutritional supplements, please refer to that chapter.

Of the 8 different forms of tocopherol, vitamin E in the natural form of d-alpha tocopherol is believed to be the most bioavailable and beneficial to the body. Good natural food sources of this include commercially available vegetable oils which are also the richest form of polyunsaturated fatty acids. Nuts are also a good source with most vegetables and meats also having small amounts.

Additional Possible Benefits of Vitamin E3

  • May reduce the risk of angina and heart attack.
  • May slow macular degeneration.
  • May prevent spinal cord damage in patients with cystic fibrosis

Recommended Dietary Intake for Vitamin E

A recent re-evaluation of dietary requirements for all vitamins and minerals was published by the National Health and Medical Research Council for Australia and New Zealand. The dietary recommendations for Vitamin E from this publication are summarised below.

Please refer to the following definitions when interpreting these recommendations:

RDI-Recommended Daily Intake
The average daily intake level that is sufficient to meet the nutritional requirements of nearly all (97-98%) health individuals in a particular life stage and gender group.

AI-Adequate Intake (used when an RDI cannot be determined)
The average daily nutrient intake level based on observed or experimentally-determined approximations or estimates of nutrient intake by a group (or groups) of apparently healthy people that are assumed to be adequate.

UL-Upper Limit of Intake
The highest average daily nutrient intake level likely to pose no adverse health effects to almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects increases.

RECOMMENDATIONS BY LIFE STAGE AND GENDER – Vitamin E
(as alpha-tocopherol equivalents)

Infants AI UL

All
0-6 months4 mg/day *
7-12 months 5 mg/day *

Children and AdolescentsAI UL

All
1-3 years 5 mg/day 70 mg/day
4-8 years 6 mg/day 100 mg/day

Boys
9-13 years 9 mg/day 180 mg/day
14-18 years 10 mg/day 250 mg/day

Girls
9-13 years 8 mg/day 180 mg/day
14-18 years 8 mg/day 250 mg/day

AdultsAI UL

Men
19-30 years 10 mg/day 300 mg/day
31-50 years 10 mg/day 300 mg/day
51-70 years 10 mg/day 300 mg/day
>70 years 10 mg/day 300 mg/day

Women
19-30 years 7 mg/day 300 mg/day
31-50 years 7 mg/day 300 mg/day
51-70 years 7 mg/day 300 mg/day
>70 years 7 mg/day 300 mg/day

Pregnancy
14-18 years 8 mg/day 300 mg/day
19-30 years 7 mg/day 300 mg/day
31-50 years 7 mg/day 300 mg/day

Lactation
14-18 years 12 mg/day 300 mg/day
19-30 years 11 mg/day 300 mg/day
31-50 years 11 mg/day 300 mg/day

*Not possible to establish. Source of intake should be breast milk, formula and food only.

Vitamin E back to Vitamins


References:
1. MacWilliam, L.D. Comparative Guide to Nutritional Supplements. Northern Dimensions Publishing, 2005.
2. Stanton R. Foods that harm, foods that heal: An A-Z guide to safe and healthy eating. Readers Digest; 2006, pp378-382.
3. Wahlqvist, M.L., et al. Australia and New Zealand: Food and Nutrition. 2nd Ed. Allen and Unwin, Sydney; 2002, pp 248-251.
4. McNamara L R. The cholesterol conspiracy 2nd Ed. OrthoMolecular Medicine 2006.
5. Rimm EB, Stampfer MJ, Ascherio A, Giovannucci E, Colditz GA, Willett WC. Vitamin E consumption and the risk of coronary heart disease in men. N Engl J Med 1993;328:1450–6.
6. Stampfer MJ, Hennekens CH, Manson JE, Colditz GA, Rosner B, Willett WC. Vitamin E consumption and the risk of coronary disease in women. N Engl J Med 1993;328:1444–9.
7. Baynes JW. Role of oxidative stress in development of complications in diabetes. Diabetes 1991;40:405–12.
8. Comstock GW, Alberg AJ, Huang HY, Wu K, Burke AE, Hoffman SC, Norkus EP, Gross M, Cutler RG, Morris JS, Spate VL, Helzlsouer KJ. The risk of developing lung cancer associated with antioxidants in the blood; ascorbic acid, carotenoids, alpha-tocopherol, selenium and total peroxyl radical absorbing capacity. Cancer Epidemiol Biomarkers Prev 1997;6:907–16.
9. Jacques PF, Chylack LT Jr. Epidemiologic evidence of a role for the antioxidant vitamins and carotenoids in cataract prevention. Am J Clin Nutr 1991;53:352S–355S.
10. National Health and Medical Research Council. Nutrient Reference Values for Australia and New Zealand. Department of Health and Ageing, Canberra 2006, copyright Commonwealth of Australia reproduced by permission.


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