What Is Tributyrin? Structure, Uses and How It Works

Tributyrin is a fat molecule made of three butyrate chains attached to a glycerol backbone, which makes it a triglyceride. When you digest it, fat-digesting enzymes called lipases cut those chains loose and release butyrate, the short-chain fatty acid that serves as the main fuel for the cells lining your colon. This guide covers tributyrin's structure in plain English, what happens to it during digestion, where it occurs naturally, what it is used for, and where the human research honestly stands.

Tributyrin structure, explained simply

Picture a short spine with three hooks. The spine is glycerol, a small molecule with three carbons. On each hook hangs one butyrate chain, a fatty acid only four carbons long. Each chain is attached to the glycerol by an ester bond, the same kind of link that holds together the fats in olive oil and butter.

That makes tributyrin a triglyceride, the same chemical family as ordinary dietary fat. The difference is chain length. The fatty acids that dominate most dietary fats, such as palmitic acid and oleic acid, have 16 and 18 carbons. Tributyrin carries three identical chains of just 4 carbons, so chemists call it a short-chain triglyceride. Those short chains are why it behaves differently from most fats, including how quickly lipases break it down.

For readers who want the chemistry: the molecular formula is C15H26O6, the molar mass is 302.36 g/mol, and the formal (IUPAC) name is 2,3-di(butanoyloxy)propyl butanoate. Its structure can also be written as the SMILES code CCCC(=O)OCC(COC(=O)CCC)OC(=O)CCC, which reads as three butyrate groups hanging off a three-carbon glycerol chain.

Other names for tributyrin

Labels and research papers use several names for the same molecule. The most common are glyceryl tributyrate, glycerol tributyrate, butyrin, tri-n-butyrin, 1,2,3-tributyrylglycerol, glycerol tributanoate and propane-1,2,3-triyl tributanoate. Its CAS registry number, the ID chemists use to avoid naming confusion, is 60-01-5.

Tributyrin key facts

What does tributyrin do in the body?

Because tributyrin is a fat, your body handles it with lipases. These enzymes cut the ester bonds step by step, adding water back at each link, until the molecule is split into glycerol and three butyrate molecules. Most fat digestion happens in the small intestine with lipase from the pancreas, but the stomach makes its own lipase too, and in a 1985 lab study, human gastric lipase was most active against tributyrin of the three fats tested.

Where the butyrate is released matters, because the colon is where butyrate does its best-known job. The honest answer is that this has not been measured directly in people, and lab models disagree. A 2023 gut model found that a fat built only from butyrate and hexanoate (a six-carbon fatty acid) was broken down quickly in the simulated stomach. A 2025 model of one branded tributyrin found that about 51 to 59 percent of the dose stayed intact through the simulated small intestine. In a small 2025 study of 10 men, blood butyrate rose later and lower after tributyrin than after sodium butyrate, which fits slower release, though it cannot tell us how much reached the colon.

Once released, butyrate is the preferred fuel of colonocytes, the cells lining the colon, and it acts as a signaling molecule for the gut lining and immune cells nearby. Our guide on what butyrate is and where it comes from covers that side of the story.

Is tributyrin found in butter?

This one is often overstated. Butter fat is the richest everyday food source of butyrate: in a Swedish analysis of dairy milk, butyric acid made up about 4% of milk fat's fatty acids by weight. But in milk fat, butyrate sits almost entirely in one end position of triglycerides whose other two positions usually carry longer fatty acids. Tributyrin needs butyrate in all three positions, so it is at most a minor part of butter.

When you read that butter is "3 to 4 percent tributyrin," the figure is really butter's butyric acid content. The tributyrin in supplements and food flavorings is made by joining glycerol with butyric acid, not extracted from butter. For what a pat of butter actually provides, see foods high in butyrate.

What is tributyrin used for?

• Dietary supplements. Tributyrin is used as a stable, low-odor way to supplement butyrate. Pure tributyrin is an oil, so it comes either as a liquid (in softgels or liquid-filled capsules) or as a dry ingredient that is only part tributyrin by weight. That is why a capsule label may list two numbers: the ingredient weight and the actual tributyrin it provides.
• Food flavoring. The FDA lists tributyrin as generally recognized as safe for use as a flavoring agent in foods such as baked goods, beverages, frozen dairy desserts and soft candy. That status covers flavoring use, not supplement doses.
• Animal feed. It is studied widely as a feed additive for pigs, poultry and calves, where researchers track growth and gut health.
• Laboratory work. Because lipases break it down so readily, tributyrin is a standard test material. Microbiologists use tributyrin agar plates to spot microbes that make fat-digesting enzymes, and enzyme researchers use it to measure lipase activity.

How tributyrin compares with sodium butyrate

Sodium butyrate is a salt with one butyrate per molecule, and it often carries the strong rancid-butter smell butyrate is known for. Tributyrin carries three butyrates on glycerol, lacks that rancid smell (chemical references describe its odor as fruity and buttery), and must be digested by lipases before any butyrate is released. Gram for gram they carry similar amounts: about 86% of tributyrin's weight is butyrate, versus about 79% for sodium butyrate. For delivery, smell and day-to-day tolerability, see the full breakdown of tributyrin vs sodium butyrate.

What the human research shows so far

Human research on tributyrin itself is thin. The first trials, in the late 1990s and early 2000s, gave doses many times larger than a supplement serving to adults with advanced cancer, to measure safety and blood butyrate levels; they were not designed to test gut health. Newer studies are small, short or industry-funded: a 2024 pilot in 24 healthy adults found 200 to 400 mg a day of a tributyrin ingredient well tolerated over three weeks, a 2025 study in 10 men compared blood levels, and a 2025 industry-funded trial tested a tributyrin and fiber blend. Most of what is known about butyrate's effects comes from studies of butyrate in general, or from animal and lab work. We grade each claim in tributyrin benefits: what the research actually shows.

Who should check with a physician first

Talk to your physician before starting tributyrin if you are pregnant, breastfeeding or planning a pregnancy, take prescription medication, or have a diagnosed digestive condition (including an inflammatory bowel condition), a liver condition or another ongoing medical condition. If you are looking for a supplement because of persistent digestive symptoms, see a physician first. Those symptoms deserve a diagnosis.

How Vita Bloom fits

Our Tributyrin contains one active ingredient: each vegetable cellulose capsule holds 550 mg of a 55% tributyrin ingredient, yielding 300 mg of tributyrin. Take one capsule daily with food, up to two a day, and give it 4 to 8 weeks of consistent use. It is odorless, vegan and gluten-free, made in the USA in a GMP-certified facility and third-party tested.

Frequently asked questions

What is tributyrin used for?

Mainly as a butyrate supplement, as a GRAS flavoring agent in foods, as an animal feed additive, and as a lab material for testing fat-digesting enzymes.

What does tributyrin do?

It delivers butyrate. Lipases split it into glycerol and three butyrate molecules, and butyrate is the main fuel for the cells lining the colon.

Is glyceryl tributyrate the same as tributyrin?

Yes. Glyceryl tributyrate, glycerol tributyrate and butyrin are all names for the same molecule, CAS number 60-01-5.

What is tributyrin oil?

Pure tributyrin is a colorless, oily liquid. Softgels carry it as a liquid, while capsules often carry a dry ingredient that is only part tributyrin, so check how much actual tributyrin the label lists.

Is tributyrin the same as butyrate?

No. Tributyrin is a carrier: three butyrates bound to glycerol. Your body has to digest it before the butyrate is free to act.

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.