[Skip to Content]

What Do Enzymes Do?

Enzymes speed up chemical reactions in our bodies. They’re an essential part of digestion, blood clotting, and growth. They also play a role in how muscles work and why diseases happen, and do many other important things.

How Are Enzymes Made?

The body makes enzymes, most of which are a special type of protein. Proteins build, maintain, and replace tissues in the body.

Enzymes also can be made in labs as dietary supplements.

How Do Enzymes Work?

Enzymes work by binding to a specific molecule in a cell and speeding up chemical reactions. The enzyme doesn’t get used up in these reactions, so it can work again and again. Some enzymes build up substances while others break them down. 

What Are Some Types of Enzymes?

Our bodies have thousands of enzymes. They include:

  • amylase, which breaks down starches
  • lipase, which breaks down fats and oils
  • protease, which breaks down proteins
  • creatine kinase (CK), which helps muscles make energy
  • aspartate aminotransaminase (AST) and alanine aminotransaminase (ALT), which help the liver change food into energy
  • thrombin, which causes blood to clot
  • glucose-6-phosphate dehydrogenase, which helps red blood cells work
  • DNA polymerase, which helps DNA (our bodies’ genetic material) copy itself so tissues can grow

What Problems Can Happen With Enzymes?

Sometimes, the body can be missing an enzyme or have too little of it. This can cause health problems. Medical conditions caused by problems with enzymes include:

  • lactose intolerance: a problem with the enzyme lactase, which causes gas, cramps, and diarrhea
  • phenylketonuria (PKU): a problem with an enzyme that breaks down an amino acid, leading to brain damage and seizures
  • Morquio syndrome: an enzyme that breaks down a type of sugar is missing or there isn't enough of it, leading to vision, hearing, bone, and heart problems
  • Tay-Sachs disease: an enzyme is missing, so fatty proteins build up in the brain and lead to damage in the brain and spinal cord
  • galactosemia: a problem with the enzymes that break down the sugar galactose, which can lead to trouble growing and gaining weight, and slowed development
  • Wilson’s disease: a problem with a liver enzyme, causing copper to build up in the liver, brain, and other organs
  • Gilbert’s syndrome: a problem with an enzyme that breaks down bilirubin, which causes jaundice (yellowing of the eyes and skin)

What Are Dietary Enzyme Supplements?

Dietary enzyme supplements are made to mimic what the body’s enzymes do. Doctors may prescribe enzyme supplements for:

  • lactose intolerance to help with gas and diarrhea
  • cystic fibrosis to help with digestion

Other enzyme supplements are advertised as ways to increase athletic performance or lose weight. These claims may be untrue and can cause health risks. Always talk to your doctor before trying any dietary supplements.

Medically reviewed by: Amy W. Anzilotti, MD
Date reviewed: January 2023