No, we cannot survive only on raw, leafy vegetables/ grass.
Humans cannot survive only on raw, leafy vegetables or grass. The grass is rich in cellulose, which is a type of carbohydrate that humans are not able to digest due to the absence of cellulose-digesting enzymes. Also, our body requires all kinds of nutrients like protein, vitamins, minerals and fats. So a human cannot survive only on raw, leafy vegetables. Besides, relative to cooked vegetables, raw vegetables cannot be digested easily.
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