Enzymes and Metabolism: Facts, Roles, and Information
Author: Disabled World (DW)
Updated/Revised Date: 2 Nov 2026
Table of Contents:
Synopsis - Definition - About This Section - FAQs - Publications - Subtopics
Synopsis
An overview of enzymes, the proteins that catalyze the body's metabolic reactions, covering how they work, their role in digestion, disease, and overall health.
At a Glance
- 1 - French chemist Anselme Payen discovered the first enzyme, diastase, in 1833.
- 2 - Enzymes are known to catalyze more than 5,000 types of biochemical reactions.
- 3 - Enzymes are found in every organ and cell of the body, including the blood, saliva, and digestive juices.
- 4 - An enzyme is usually named after its substrate or the reaction it catalyzes, with the name ending in -ase.
Topic Definition
- Enzymes and Metabolism
Enzymes are molecules, most of them proteins, that speed up or catalyze the chemical reactions the body relies on to stay alive. In each reaction the starting molecules, called substrates, are bound by an enzyme and converted into new molecules called products, and the particular set of enzymes a cell makes determines which metabolic pathways can run inside it. Because metabolism is essentially a vast, continuous series of chemical reactions, enzymes act as the catalysts that make those reactions fast and efficient enough to sustain life. They are found in every organ and cell, where they break down food so the body can use it, help blood to clot, build and repair tissues, and carry out countless other tasks. The body makes the enzymes it needs, and a shortage of one particular enzyme, such as lactase, can cause specific health problems.
Overview
What are Enzymes?
Enzymes are molecules, almost all of them proteins, that speed up (catalyze) chemical reactions in the body. In each reaction, the starting molecules, called substrates, are changed by the enzyme into new molecules, called products. Almost all of the chemical processes in a cell need enzymes to happen fast enough to sustain life, and the set of enzymes a cell makes decides which metabolic pathways can run in that cell. The study of enzymes is called enzymology.
Enzymes are needed for all body functions and are found in every organ and cell, including in the blood, saliva, stomach juices, and intestinal fluids. For example, they break down the food we eat so the body can use it, and blood clotting is another example of enzymes at work [MedlinePlus, 2025].
The human body's metabolic system is a huge series of linked chemical reactions, and enzymes act as the catalysts that make those reactions efficient. Each enzyme usually works on one substrate or one type of reaction, because its three-dimensional shape fits only certain molecules.
Digestive Enzymes
Digestion depends on enzymes the body makes itself. Amylase in saliva and from the pancreas breaks down starches, proteases such as pepsin in the stomach and trypsin from the pancreas break down proteins, and lipase breaks down fats. The small intestine also makes enzymes such as lactase, which breaks down the milk sugar lactose. A healthy body makes the digestive enzymes it needs and does not depend on enzymes from food.
Enzymes and Health
When the body does not make enough of a particular enzyme, health problems can follow. People with lactase deficiency may have bloating, gas, or diarrhea after dairy foods. Some inherited conditions, such as phenylketonuria (PKU) and lysosomal storage diseases like Gaucher disease, are caused by a missing or faulty enzyme, and some of them are treated with enzyme replacement therapy. People whose pancreas does not make enough digestive enzymes, for example because of cystic fibrosis or chronic pancreatitis, may need prescription pancreatic enzyme medicine.
Doctors also measure enzymes in the blood to check health. For example, raised levels of liver enzymes can be a sign of liver inflammation or damage.
Enzyme Supplements and Raw Food
Cooking deactivates many enzymes in food, and some supplement makers claim that people need extra enzymes from raw food or pills to stay healthy. The body makes the enzymes it needs, so food enzymes are not required for digestion. Enzyme supplements do help with specific problems, such as lactase tablets for lactose intolerance or prescription pancreatic enzymes, and anyone thinking of taking an enzyme supplement should talk with a doctor first.
Enzymes: Facts
- French chemist Anselme Payen discovered the first enzyme, diastase, in 1833.
- Enzymes are known to catalyze more than 5,000 types of biochemical reactions.
- Some enzymes are used commercially, for example in making antibiotics and in laundry detergents.
- An enzyme's name usually comes from its substrate or the reaction it catalyzes, and it ends in -ase.
- Most enzymes are proteins, although a few are catalytic RNA molecules.
- Enzymes must bind their substrates before they can catalyze a chemical reaction.
- Enzyme kinetics is the study of how enzymes bind substrates and turn them into products.
- Several enzymes can work together in a set order, forming metabolic pathways.
- Coenzymes are small organic molecules, often made from vitamins, that help enzymes work by carrying chemical groups from one enzyme to another.
Frequently Asked Questions
What is the difference between digestive and metabolic enzymes?
Digestive enzymes break food down in the gut so nutrients can be absorbed, while metabolic enzymes drive the chemical reactions inside cells that produce energy and maintain body functions.
Should I take enzyme supplements?
Enzyme supplements may help some people with digestive issues, but they are not needed by everyone, so it is best to speak with a doctor before adding them to your routine.
What are the three main types of digestive enzymes?
The main digestive enzymes are amylase, which breaks down carbohydrates, protease, which breaks down proteins, and lipase, which breaks down fats.
Does cooking really destroy enzymes in food?
Heat above roughly 118 degrees Fahrenheit deactivates many enzymes in food, which is why raw and fresh foods retain more of their natural enzyme content than cooked or processed ones.
What causes low enzyme levels in the body?
Enzyme activity can be affected by aging, certain illnesses, digestive disorders, and a diet heavy in cooked and processed foods, though the body still produces enzymes of its own.
Are enzymes and probiotics the same thing?
No, enzymes are proteins that speed up chemical reactions, while probiotics are live beneficial bacteria, though both can play a role in supporting healthy digestion.
Can enzymes affect how the body stores fat?
Enzymes help digest food efficiently, which can influence how much is converted into fat, though they are not weight loss agents and work best alongside a balanced diet.
What is lactase deficiency?
Lactase deficiency means the small intestine makes too little of the enzyme lactase, which breaks down milk sugar, causing bloating, gas, and diarrhea after dairy. Lactase supplements and lactose-free products can help.
References
- MedlinePlus. (2025). Enzyme. National Library of Medicine.
Curated and edited by Ian C. Langtree, Founder and Editor-in-Chief, Disabled World. This section is maintained by the Disabled World editorial team. Last updated: