Enzymes are proteins that help speed up chemical reactions in our bodies. Enzymes are essential for digestion, liver function and much more. Too much or too little of a certain enzyme can cause health problems. Enzymes in our blood can also help healthcare providers check for injuries and diseases.

What are enzymes?

Enzymes are proteins that help speed up metabolism, or the chemical reactions in our bodies. They build some substances and break others down. All living things have enzymes.

Our bodies naturally produce enzymes. But enzymes are also in manufactured products and food.


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What do enzymes do?

One of the most important roles of enzymes is to aid in digestion. Digestion is the process of turning the food we eat into energy. For example, there are enzymes in our saliva, pancreas, intestines and stomach. They break down fats, proteins and carbohydrates. Enzymes use these nutrients for growth and cell repair.

Enzymes also help with:

  • Breathing.
  • Building muscle.
  • Nerve function.
  • Ridding our bodies of toxins.

What are the different types of enzymes?

There are thousands of individual enzymes in the body. Each type of enzyme only has one job. For example, the enzyme sucrase breaks down a sugar called sucrose. Lactase breaks down lactose, a kind of sugar found in milk products.

Some of the most common digestive enzymes are:

  • Carbohydrase breaks down carbohydrates into sugars.
  • Lipase breaks down fats into fatty acids.
  • Protease breaks down protein into amino acids.

Parts of Enzymes


What are the parts of an enzyme?

Each enzyme has an “active site.” This area has a unique shape. The substance an enzyme works on is a substrate. The substrate also has a unique shape. The enzyme and the substrate must fit together to work.

How do temperature and pH affect enzymes?

Enzymes need the right conditions to work. If conditions aren’t right, enzymes can change shape. Then, they no longer fit with substrates, so they don’t work correctly.

Each enzyme has an ideal temperature and pH:

  • pH: Enzymes are sensitive to acidity and alkalinity. They don’t work properly if an environment is too acidic or basic. For example, an enzyme in the stomach called pepsin breaks down proteins. If your stomach doesn’t have enough acid, pepsin can’t function optimally.
  • Temperature: Enzymes work best when your body temperature is normal, about 98.6°F (37°C). As temperature increases, enzyme reactions increase. But if the temperature gets too high, the enzyme stops working. That’s why a high fever can disrupt bodily functions.

Common Conditions & Disorders


What health conditions can enzyme problems cause?

Metabolic disorders are often the result of not having enough of a certain enzyme. Parents can pass them to their children through genes (inherited). Some examples of inherited metabolic disorders include:

  • Fabry disease prevents body from making enzymes (alpha-galactosidase A) that break down fat (lipids).
  • Krabbe disease (globoid cell leukodystrophy) affects enzymes needed for the protective covering (myelin) on nerve cells (Central Nervous System).
  • Maple syrup urine disease affects enzymes needed to break down certain branch chain amino acids.

Other health conditions related to enzyme imbalances include:

How are enzyme tests used to diagnose health conditions?

Your healthcare provider can use a variety of enzyme and protein blood tests to check for certain health conditions. For example, elevated liver enzymes could be a sign of liver disease.

Caring for Your Enzymes

Do I need to take enzyme supplements?

People without chronic health conditions can usually get the enzymes they need from a healthy diet. But, if you have certain health conditions, your healthcare provider may recommend taking enzyme supplements. For instance, many people with EPI may take a digestive enzyme before they eat. This helps their bodies absorb nutrients from food. Talk to your healthcare provider before taking any type of enzyme supplement.

Can medications affect enzyme levels?

Some medications affect enzyme levels. For example, antibiotics can kill certain bacteria needed for some enzymes to work their best. This is the reason antibiotics may cause diarrhea. To kill the bacteria making you sick, they also wipe out important good bacteria that aid in digestion.

Statins (medications that lower cholesterol) can raise liver enzymes and muscle enzymes. They may increase the risk of damage to the liver or muscles.

When to Call a Doctor

When should I contact my doctor about an enzyme problem?

You won’t know if you have an enzyme problem without a blood test. Contact your doctor if you experience any of the following problems:

A note from Cleveland Clinic

Enzymes help facilitate biochemical reactions in our bodies. They aid in everything from breathing to digestion. Having too little or too much of a certain enzyme can lead to health problems. Some people with chronic conditions may need to take enzyme supplements to help their bodies work as they should. Only take enzyme supplements under the supervision of your healthcare provider.

Medically Reviewed

Last reviewed on 05/12/2021.

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