LETTERS

摘要

Hal Hodson suggests that it might not be possible to conduct a randomised clinical trial of the ketogenic diet which involves cutting back on carbohydrates and increasing fat intake, for the treatment of brain cancer (27 February, p 10). While people would of course know what diet they were on, so the trial could not be "blind", randomised trials of diets have been done, such as those of the Mediterranean diet. Instead of giving a sample of people such a diet and monitoring them for two years, as suggested by an oncologist interviewed for the article, I think it would be better to place half of a sample of, say, 50 people at random on the diet, and half not. This would allow a clear comparison of recurrence rates in the two groups. If instead we follow the design outlined in the article, it would not be possible to determine whether any reduction in recurrence of cancer was due to patient selection or the effects of the diet itself.