一，eat是动词，应该用副词healthily，如果后面要加名词，那就是eat healthy是对的。举例说明：
1，we should eat healthy food.我们应该吃健康的食物。这里healthy是形容词用来修饰名词food.
2，We should eat healthily.我们吃的很健康。这里副词healthily修饰eat.
二，eating可当名词后面用名词health当饮食健康讲。
healthy 释义：
adj. 健康的，健全的；有益于健康的
例句：
A healthy body is the best wealth.
一个健康的身体是最好的财富。
词组：
healthy life健康人生
healthy food有益健康的食物
keep healthy保持健康
eating 释义为
adj. 食用的；可食的
n. 吃；食物
动词eat的现在分词形式.
habits释义：
n. 习惯（habit的复数）；[生物] 习性
n. (Habits)人名；(匈)豪比奇
例句：
His personal habits put them off.
他的个人习惯让他们反感。
1/eating healthy释义：
健康饮食
2/eating healthy英语作文例句：
There are no special medicines that can make it happen sooner! Eating healthy foods and exercising more can make all children feel better.
没有特殊的药物可以使它发生得更快！吃健康的食物和多锻炼可以让所有的孩子感觉更好。
Eating healthy is very important to our daily lives. Not only do we need to intake enough meat and vegetables, but also sufficient carbohydrate and protein. In addition, we should never skip any meal, each meal can help us to stay energetic and concentrated.
Diet 是饮食的意思，而healthy eating habits 则是健康饮食习惯的意思，区别可以从以下例子看出：
If you want to have healthy eating habits, you need to change your diet, don't eat so much outside, cook at home. 如果你想拥有健康的饮食习惯，你需要改变你的饮食，不要在外面吃那么多，在家做饭。