Lipase and fat digestion: how fats are broken down

Olive oil on bread, tahini in a salad dressing, butter in pastry, the fat in a piece of lamb: fat is part of many meals, and it is handled differently from protein or starch. To break it down, the body uses two helpers together: bile and lipase.

This article explains what dietary fats are, how bile and lipase break them down, and where the lipase in Goodness Digestive Enzymes fits in.

What are dietary fats?

The US National Library of Medicine (MedlinePlus) describes fats as a type of nutrient you get from your diet. It is essential to eat some fat, and harmful to eat too much. Fat supplies two essential fatty acids, linoleic acid and linolenic acid, which the body cannot make itself.

Fat is also dense in calories. According to MedlinePlus, fat has 9 calories per gram, more than twice the 4 calories per gram in carbohydrates and in protein.

All fats are made up of saturated and unsaturated fatty acids, in different proportions. MedlinePlus describes how to tell them apart in the kitchen:

MedlinePlus advises choosing fats from vegetable sources, such as olive oil, more often than fats from animal products, and avoiding foods made with hydrogenated or partially hydrogenated oils.

What does fat break down into?

According to NIDDK, part of the US National Institutes of Health (NIH), digestion breaks fats into fatty acids and glycerol.

Most of the fat in food is in the form of triglycerides: three fatty acids attached to a backbone of glycerol. A 2013 review of enzymes in the journal BioMed Research International explains that pancreatic lipase, the main enzyme that breaks down dietary fats in the human digestive system, converts the triglycerides in the oils we eat into a monoglyceride and two free fatty acids.

What does bile do?

Bile is not an enzyme, and it does not split fat itself. It is a digestive juice made by the liver. MedlinePlus describes bile as a fluid made and released by the liver that helps with digestion, and lists bile acids, also called bile salts, among its contents.

The NIH explains the timing. Bile helps digest fats and some vitamins. Between meals, it is stored; when you eat, it is squeezed through the bile ducts into the small intestine, where the fat in your meal is waiting.

A 2021 review of bile acids in the International Journal of Molecular Sciences describes what happens next. Bile acids emulsify dietary fat: they break it into small droplets spread through the watery contents of the gut. Lipase can only work at the surface of these droplets. Bile acids clear that surface of other substances and help lipase settle into place, so that it can reach the fat.

Where does the body's lipase come from?

Your main source of lipase is the pancreas. MedlinePlus describes lipase as a protein, an enzyme, released by the pancreas into the small intestine. The NIH adds that the juice from the pancreas carries enzymes for carbohydrates, fats and proteins, and reaches the small intestine through small ducts.

The 2013 review notes that the stomach makes a lipase of its own, gastric lipase. But it names pancreatic lipase as the main enzyme for breaking down dietary fats.

How do bile and lipase work together?

The two meet in the small intestine. According to the NIH, the muscles of the small intestine mix food with digestive juices from the pancreas, the liver and the intestine itself, and these juices together complete the breakdown of fats, as well as proteins and carbohydrates.

In short:

1. Fat arrives in the small intestine from the stomach.
2. Bile from the liver is released into the small intestine. Its bile acids break the fat into small droplets and clear the droplet surface, so that lipase can reach the fat.
3. Lipase from the pancreas settles on the droplets and splits the fat into fatty acids and monoglycerides.
4. Bile acids then gather these products into tiny clusters, called mixed micelles, and carry them away from the droplets.

Each has its own role: bile prepares the fat, and lipase is the enzyme that does the chemical cutting.

Where does the lipase in a supplement come from?

Lipase is not unique to people. The 2013 review describes lipases as having essential roles in the digestion and handling of dietary fats and oils in most, if not all, living things, including bacteria and fungi.

That is why lipase for food use can be produced by microorganisms. Both the 2013 review and a 2025 review of food enzymes in Food Science & Nutrition list bacteria and fungi as sources of lipase. The food industry uses lipase too: according to the 2025 review, it breaks down milk fat and helps develop the flavour of cheese.

All 13 enzymes in Goodness Digestive Enzymes come from microbial and plant sources.

Where does lipase fit in Goodness Digestive Enzymes?

In Goodness Digestive Enzymes, lipase helps break down fats and oils. It makes up the fats group on its own, alongside three other groups for protein, starch and sugars, and plant fibre:

• Protein enzymes: protease, bromelain and papain
• Carbohydrate enzymes: amylase, lactase and more
• Fibre enzymes

Fat rarely comes on its own. A rich family meal combines meat, rice cooked in butter or oil, yoghurt and bread, so all four groups of food arrive together. For timing, read When should you take digestive enzymes?; the How to use page has the directions and safety notes, and the Ingredients page lists every enzyme.

Goodness Digestive Enzymes is a food supplement that supports healthy digestion. It does not replace a varied, balanced diet.