An apple a day keeps the doctor away is a popular proverb which that means eating healthy foods will keep one from getting sick (and needing to see a doctor).

For example:

My grandmother always told me, ‘An apple a day keeps the doctor away,’ so I make sure to eat one every morning. 

In the spirit of that old saying, ‘An apple a day keeps the doctor away,’ I’m packing apples for my lunch. 

While not scientifically proven, the proverb ‘An apple a day keeps the doctor away’ encourages a healthy habit of eating fruits. 

Remember, even if it’s just an old adage, ‘An apple a day keeps the doctor away’ highlights the value of healthy eating. 

Since I started eating an apple every day, I’ve noticed I feel healthier, living by the idea that an apple a day keeps the doctor away. 

Tradução:

An apple a day keeps the doctor away vem de um provérbio em inglês que significa literalmente que uma maçã por dia mantém o médico afastado. Ou seja, uma alimentação saudável, simbolizada pela maçã, promove a boa saúde e reduz a necessidade de consultas médicas