There are hundreds of different enzymes but to simplify things we are going to talk about three of them.
Amylase
This enzyme breaks down carbohydrates (sugars and starch in fruits, vegetables, wheat, dairy etc.) and converts them to sugars or glucose.
Digestion with amylase begins in the mouth with saliva when you chew food. This is why you can hear the echo of mother in the back of your mind telling you to chew your food 27 times before swallowing. But she was right. The more you chew, the more amylase you have breaking down carbs for better absorption.
Protease
Protease is the enzyme that breaks down protein. This is an important enzyme and works with the hydrochloric acid in the stomach to convert protein into amino acids that can then be absorbed through the intestines.
It can also breakdown certain viruses and bacteria and this is an important function because a lack of protease can reduce the ability of the immune system.
Lipase
Lipase is the enzyme that along with bile, breaks down fat into fatty acids and glycerol. This is a very important function because when fat cannot be broken down properly you can end up with elevated cholesterol and triglycerides and have difficulty losing weight. Although it is easy to consume too much fat, the other side of the coin is that the body needs a certain amount of fats to stay healthy.
These three enzymes breakdown the majority of the foods you eat and are necessary for proper digestion. A lack of any of them can cause problems with your body.
Sometimes symptoms of associated with lack of these enzymes can be confused with something else and you end up not getting the results you wanted.
Something as simple as taking enzyme supplements can resolve issues you may have with your body. Of course you want to check with your health care provider about any enzymes supplementation.