What Is Protease? The Enzyme That Digests Protein

Protease is a digestive enzyme that breaks down the protein in your food into smaller pieces, such as amino acids (1). In your body, proteases work in your stomach and your small intestine (1), so you can absorb the protein from foods like meat, fish, eggs, and beans.

This page is part of our guide to digestive enzymes. Below you will learn what protease is, what it does, which foods it works on, and where you find it in our products.

written and reviewed by Anouk Martini (registered dietician)

Knowledge bank

In short

Protease is the name for enzymes that break protein down into smaller pieces (1).
Your stomach and your pancreas make proteases, and your small intestine completes the job (1).
Your body absorbs the amino acids and uses them for energy, growth, and cell repair (1).
Protease is in our products Lipase Mix and Enzymix.

What is protease?

Protease is the name for enzymes that split proteins. Proteins are long chains of amino acids, and foods such as meat, fish, eggs, legumes, and nuts are rich in them. Your body has to cut those chains into smaller pieces before it can absorb them (1).

Protease is really a family of enzymes, which is why you also see the word proteases. Pepsin, trypsin, and chymotrypsin are well-known digestive proteases (2). The protease in our products is not animal-derived, and both products are suitable for vegans.

What does protease do in the body?

Protease works along your digestive tract:

In your stomach. Glands in your stomach lining make stomach acid and enzymes that break down food, including protein (1). The best-known one is pepsin (2).
In your pancreas and small intestine. Your pancreas makes a digestive juice with several enzymes that break down proteins, fats, and carbohydrates, and sends it to your small intestine (1). Trypsin and chymotrypsin are two of them (2).
Finishing the job. Your small intestine completes the breakdown of proteins (1).
Absorption. Your small intestine absorbs the amino acids. Your blood carries them to your liver, which delivers nutrients to the rest of your body when needed (1).

Which foods does protease work on?

Protease works on the protein in your food. Foods that contain a lot of protein include:

Meat and poultry
Fish
Eggs
Legumes such as beans and lentils
Nuts

When might extra protease help?

Your body makes its own proteases, so most people never have to think about them. Age, diet, lifestyle, and stress can affect how well digestion works, and so do the size and type of a meal. Some people take a protease supplement with protein-rich meals or meals that mix nutrients, such as pizza or lasagna (fats, carbs, and proteins) or nuts and cheese (fats and proteins). Protease supports the breakdown of proteins found in foods like meat, fish, eggs, and legumes.*

Not sure whether a supplement fits you? Talk to a doctor or dietitian.

Where is protease in our products?

Protease is in two Intoleran products:

Lipase Mix provides a focused blend of lipase, amylase, and protease (75,000 HUT) to support comfortable digestion of fats and everyday meals.* The capsules can be opened and mixed with food, so Lipase Mix suits children ages 2 and up. It is vegan and free from gluten and soy.
Enzymix is a blend of nine digestive enzymes that support the breakdown of carbohydrates, proteins, fats, lactose, and plant fibers.* Its protease (75,000 HUT) supports the breakdown of proteins found in foods such as meat, fish, eggs, legumes, and nuts.* Enzymix is suitable for vegetarians and vegans and free of gluten and soy.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Not sure which enzyme you need?

Digestive enzymes each have their own job. Answer a few questions in our supplement advisor and see which products fit your situation. You can also ask our dietitians a question.

When should you talk to a doctor or dietitian?

Do your symptoms persist, are you losing weight without trying, or are you cutting out more and more foods? Talk to your doctor or a dietitian. A supplement does not replace medical advice.

Protein is only one part of a meal. Lipase helps break down fat. See all of our digestive enzymes.

Sources

National Institute of Diabetes and Digestive and Kidney Diseases. Your digestive system & how it works [Internet]. Bethesda (MD): National Institute of Diabetes and Digestive and Kidney Diseases; last reviewed 2017 Dec. Available from: https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works
Hernández-Pérez T, Paredes-López O. Ancient Latin-American food crops: an overview of their nutraceutical and antiobesity peptides. Food Sci Technol Int. 2025;32(4):454-64. doi:10.1177/10820132251319934