group (therefore, for vitamin E the RDA is 120 percent of the EAR). The calculated RDA in milligrams is rounded down.

RDA for Lactation

 

14–18 years

19 mg (44.2 µmol)/day of α-tocopherol

19–30 years

19 mg (44.2 µmol)/day of α-tocopherol

31–50 years

19 mg (44.2 µmol)/day of α-tocopherol

Special Considerations
Chronic Diseases

Data related to the effects of vitamin E on morbidity and mortality from chronic disease in the United States and Canada are limited. The evidence is strongest for prevention of coronary heart disease (CHD). However, even for this outcome, four double-blind, place-bo-controlled trials have been reported, and only one of four, the Cambridge Heart Antioxidant Study (CHAOS) (Stephens et al., 1996), with prevention of heart disease as its primary aim, had a positive outcome. Two of the other trials, the GISSI-Prevenzione Trial and the Heart Outcomes Prevention Evaluation (HOPE) Study (GISSI-Prevenzione Investigators, 1999; HOPE Study Investigators, 2000), with prevention of heart disease as their primary aim, had neutral results. Similarly, the fourth trial, the Alpha-Tocopherol Beta-Carotene (ATBC) Cancer Prevention Study (ATBC Cancer Prevention Study Group, 1994), which had lung cancer as its primary outcome, reported no beneficial effect of vitamin E on myocardial infarction rates. Thus, a recommendation of high vitamin E intakes for the general population to decrease CHD risk is considered premature.

Some physicians caring for patients with coronary artery disease are already prescribing vitamin E at doses used in the CHAOS study, 400 or 800 IU (268 or 567 mg)/day of RRR-α-tocopherol. Precisely how vitamin E works at these high doses is not known but could include both antioxidant and nonantioxidant mechanisms. This is an active research area at both the molecular and the clinical levels, and further research is needed.

Currently, a number of other double-blind, placebo-controlled intervention trials of the efficacy of vitamin E to prevent or ameliorate CHD are in progress. If these studies result in positive outcomes, it may become necessary to review the recommendations for vitamin E intakes in some subgroups of the adult populations, especially those in the groups over 50 years of age because increasing age is an important risk factor for heart disease. Although there is a



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