Vitamins E and C are safe across a broad range of intakes1,2
John N Hathcock, Angelo Azzi, Jeffrey Blumberg, Tammy Bray, Annette
Dickinson, Balz Frei, Ishwarlal Jialal, Carol S Johnston, Frank J
Kelly, Klaus Kraemer, Lester Packer, Sampath Parthasarathy, Helmut Sies
and Maret G Traber
1 From the Council for Responsible Nutrition, Washington, DC (JNH and
AD); the University of Bern, Bern, Switzerland (AA); Tufts University,
Boston, MA (JB); Oregon State University, Corvallis, OR (TB, BF, and
MGT); the University of California, Davis, Davis, CA (IJ); Arizona
State University, Mesa, AZ (CSJ); King's College, London, United
Kingdom (FJK); BASF, Ludwigshafen, Germany (KK); the University of
Southern California, Los Angeles, CA (LP); Louisiana State University,
Baton Rouge, LA (SP); and Heinrich Heine University, Dusseldorf,
Germany (HS).
A robust database shows that dietary supplements of vitamins E and C
are safe for the general population. Because these nutrients supply
antioxidant and other functions for homeostasis and protection against
free radical damage, supplementation has been intensively studied.
Because of perceived benefits, many persons consume quantities of
vitamins E and C well above the recommended dietary allowances. As
safety guidance, tolerable upper intake levels have been established by
the Food and Nutrition Board, Institute of Medicine, at 1000 mg for
vitamin E and 2000 mg for vitamin C in adults. Many clinical trials
with these vitamins have involved subjects with various diseases, and
no consistent pattern of adverse effects has occurred at any intake.
Numerous studies of vitamin C supplementation have provided no pattern
of evidence to support concerns about safety other than occasional
gastrointestinal upset or mild diarrhea resulting from the osmotic
effects of unabsorbed quantities of vitamin C. Evidence of bleeding
effects and other potential adverse effects of high vitamin E intakes
in humans is not convincing. Evidence of adverse effects of vitamin C
that result from its effects on iron absorption and metabolism has not
been confirmed in clinical trials. Thus, we conclude from clinical
trial evidence that vitamin E supplements appear safe for most adults
in amounts 1600 IU (1073 mg RRR--tocopherol or the molar equivalent of
its esters) and that vitamin C supplements of 2000 mg/d are safe for
most adults.
Copyright © 2005 by The American Society for Nutrition
Vitamins E and C are Safe Across Broad Range of Intakes 
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