Apples are considered a nutritious food; so this expression is intended as advice. To stay healthy (and to not have to visit the doctor) you should eat healthy food like, an apple, every day.

苹果富含营养，所以这种表达代表一种建议。要保持健康(不用看医生)你应该每天吃苹果这样的健康食物。

youdao

First and foremost, you should eat more healthy food like vegetables and fruits and avoid junk food.

首先，你应该多吃一些健康的食物，例如蔬菜和水果，不要吃垃圾食品。

youdao

With so many food programmes and books telling you what you should and shouldn't eat to be healthy it's hard to keep track.

由于太多的饮食节目和书籍会提醒您，什么应该吃或不吃，以保持健康，所以很难有章可循。

youdao