The liver is the human digestive organ that produces bile, a fluid that helps digest fats.
Bile is made continuously by liver cells and is stored and concentrated in the gallbladder. When fatty food enters the small intestine, the gallbladder can release bile through the bile duct. Bile salts break large fat globules into smaller droplets, a process called emulsification, making fats easier for digestive enzymes to process.
The liver has many other roles. It processes nutrients absorbed from the intestine, stores glycogen and certain vitamins, makes important blood proteins, and chemically modifies or removes many substances from the blood. It also helps convert ammonia, a toxic waste product, into urea for excretion by the kidneys.
A common mistake is to say that the gallbladder produces bile. It does not; it stores and concentrates bile made by the liver. The pancreas contributes digestive enzymes and bicarbonate, but it is not the organ that manufactures bile.