. . . does NOT keep the doctor away, according to a recent University of Michigan study.
The aphorism is based on a 150-year-old Welsh rhyme: "Eat an apple on going to bed and you'll keep the doctor from earning his bread."
The researchers in Ann Arbor at the U. of Michigan University School of Nursing decided the proverb had been unquestioned long enough and it was now time to subject it to some scientific scrutiny.
The scientists compared daily apple eaters to non-apple eaters, and defined "keeping the doctor away" as one visit to a physician per year.
The result? There was no statistically meaningful difference in visits to the doctor between the apple eaters and non-eaters after various factors were controlled for. However, there was one meaningful difference between the two groups: Apple eaters were somewhat more likely to avoid prescription drug use. Which means the saying should really be changed to: "An apple a day keeps the pharmacist away!"