When we eat raw foods the enzymes in the food are activated by heat and moisture in the mouth. Once active, these enzymes digest a significant portion of our food and make it small enough to pass through the villi (small projections found in the small intestines) and into the blood. Metabolic enzymes found in the blood then take the digested 45 known nutrients and build them into muscles, nerves, bones, blood, lungs, and various glands. Every cell in the body which is referred to as enzyme specificity. A protein digestive enzyme will not digest a fat and a fat enzyme will not digest starch. Enzymes act upon chemicals and change them into another chemical, but remain unchanged themselves. Simply stated our chemicals are changed from their original identity by the enzyme to another chemical with a different identity. Without enzymes nothing in our body would work.