Do Fruits and Vegetables Prevent Cancer Recurrence?

Oh that nutrition and health were that simple. The The WHEL trial results appeared yesterday in JAMA. The sadly disappointing results of that trial showed no difference in rates of breast cancer recurrence among women who typically ate 5 servings of fruits and vegetables every day as compared to those who ate nearly twice that amount. I served on the data management committee for this trial and was involved with it for more than 10 years–a fascinating experience and a long saga.  I thought the trial was exceptionally well done. The investigators monitored fruit and vegetable intake by measuring the amounts of carotenes and other nutrients in the blood of the participants. Although there was some convergence of dietary patterns over the 8 years of study, the patterns were distinct enough to show benefits from eating more fruits and vegetables if that had been the case. An accompanying editorial explains why sorting out diet and cancer risk is so complicated. In the meantime, what to do? We know that people who habitually eat fruits and vegetables are healthier than those who don’t. The old “five-a-day” is a reasonable goal and it’s too bad that the promoters of that message messed it up by turning it into “fruits & vegetables: more matters.” As with most things in nutrition, enough is enough and more is not necessarily better.