Intakes of carotenoids, vitamin C, and vitamin E and MS risk among two large cohorts of women

Background
Antioxidant nutrients may reduce the risk of MS. In a recent case-control study, vitamin C intake was significantly inversely associated with MS risk among women. However, no prospective data are available.

Objective
To examine prospectively the associations of intakes of carotenoids, vitamin C, and vitamin E with the risk of MS among women.

Methods
The authors documented the occurrence of definite and probable MS within two large cohorts of women who completed detailed and validated semiquantitative food frequency questionnaires. One cohort (Nurses' Health Study) comprised 81,683 women aged 38 to 63 years in 1984, who were followed for 12 years; the other (Nurses' Health Study II) comprised 95,056 women aged 27 to 44 years in 1991, who were followed for 6 years.

Results
The authors documented a total of 214 cases of MS. After adjustments for age, latitude of birthplace, pack-years of smoking, and total energy intake, the pooled multivariate relative risks (95% CIs) comparing women in the highest quintile with those in the lowest quintile were 1.1 (0.7 to 1.7) for alpha-carotene, 1.1 (0.7 to 1.6) for beta-carotene, 1.4 (0.8 to 2.2) for beta-cryptoxanthin, 1.0 (0.6 to 1.5) for lycopene, 1.0 (0.7 to 1.6) for lutein/zeaxanthin, 1.4 (0.9 to 2.1) for total vitamin C, 1.3 (0.9 to 2.0) for dietary vitamin C, 0.8 (0.6 to 1.3) for total vitamin E, and 0.9 (0.6 to 1.4) for dietary vitamin E. The authors found no associations between intakes of fruits and vegetables and risk of MS. Use of vitamin C, vitamin E, and multivitamin supplements was also unrelated to risk of MS.

Conclusions
These findings do not support hypotheses relating higher intakes of dietary carotenoids, vitamin C, and vitamin E to reduced risk of MS in women.