A new prospective study has reported that vegetable consumption reduces the risk of breast cancer recurrence, especially among tamoxifen users. The protective effect of vegetables on the risk of breast cancer recurrence has not been established. Previous reports of anti-cancer activity of phytochemicals in cruciferous vegetables in combination with tamoxifen led the authors to include a specific evaluation of this class of vegetables in the study. The study included 3,080 breast cancer survivors enrolled in the Women's Healthy Eating and Living Study. Estimates of vegetable intake was based on repeated 24-hour dietary recalls. The women had been diagnosed approximately two years previously, on average, at time of enrollment. Participants reported baseline average intakes of 3.1 servings per day of vegetables, and 0.5 servings per day of cruciferous vegetables. Vegetable intake was divided into thirds.

Vegetable intake in the highest compared to the lowest thirds was found to be associated with a 31% lower risk of breast cancer recurrence. Among women taking tamoxifen, high overall vegetable intake was associated with a 44% lower risk of recurrence. The risk was even lower among women taking tamoxifen who had above median cruciferous vegetable intake as well as being within the highest third of total vegetable intake. The authors conclude that vegetable consumption may be associated with a reduction in the risk of breast cancer recurrence, particularly for those using tamoxifen. However, it is possible that vegetable intake is simply a surrogate for other health-promoting behaviors.