Here's why you can't "Digest" Grass?

Grass is composed of cellulose, a polysaccharide found in plants. Humans lack the enzyme necessary to digest cellulose, so we are unable to break it down into a form our body can use to gain energy. Our digestive system is designed to break down proteins and carbohydrates, both of which are found in grass, but not in a form that can be readily absorbed by our bodies. In addition, grass contains a number of vitamins and minerals, but these cannot be absorbed by our bodies either, since our digestive system is not designed to process them.

The only way for humans to gain any nutritional benefit from grass is to break it down into smaller components that can be absorbed by our bodies. This process is called fermentation, and it requires the presence of microorganisms such as bacteria and fungi. These microorganisms are able to break down the in the grass into simpler sugars, which can then be absorbed by the human body. While this process provide some nutritional benefit, it is not as efficient as simply eating other types of food that are more easily digested.