The aphorism, "An apple a day keeps the doctor away" was coined in 1913 but similar advice first appeared in print in 1866, both based on a proverb from Pembrokeshire, Wales "Eat an apple on going to bed and you'll keep the doctor from earning his bread." But the Norse got there first.
In the mythology of the northern Germanic peoples, the goddess Iðunn distributed apples to the Æsir at their evening feasts that enabled them to remain ever youthful. But, not for the first time, we are getting ahead of our story.