Source: The American Society for Clinical Nutrition, Inc.

Vitamins E and C are safe across a broad range of intakes 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 Am J Clin Nutr 2005;81 736-745

http://www.ajcn.org/cgi/content/abstract/81/4/736

http://www.ajcn.org/cgi/content/full/81/4/736

http://www.ajcn.org/cgi/reprint/81/4/736

American Journal of Clinical Nutrition, Vol. 81, No. 4, 736-745, April 2005