The liver works around the clock to keep us healthy. Its primary functions are bile production and excretion, bilirubin, cholesterol, hormones, and drugs excretion, metabolism of fats, proteins, and carbohydrates, enzyme activation, glycogen storage, vitamins A, D, E, K, B12, and minerals storage, and synthesis of plasma proteins, such as albumin and clotting factors.
While the liver (along with the pancreas and gallbladder) is not part of the digestive system, it plays a vital role as food is digested and goes from top to bottom. Anything we eat, whether food, alcohol, medicine, or toxins, gets filtered by the liver. Once we ingest food, it is digested by the stomach and intestine, absorbed into the blood, and goes to the liver.
The liver’s primary role is to process materials absorbed by the small intestine and produce the necessary chemicals. The liver is the chemical factory of the body. It processes nutrients so that the rest of the body can use them. It also produces albumin, which enters the bloodstream and helps keep fluid from leaking out of the blood vessels into other tissues. It also carries hormones, vitamins, and enzymes throughout the body. Without enough albumin, fluid can leak out of the blood and build up in the lungs, abdomen (Ascites), or other body parts.
The liver also creates bile, which converts excess carbohydrates and proteins and stores them for later use. Bile is essential for digestion. It helps the body absorb fat into the bloodstream and carries unusable waste products and toxins out of the body through the stool. Bile is composed mainly of water electrolytes and other substances, including bile salts, cholesterol, bilirubin, lecithin, amino acids, drugs, toxins, heavy metals, and vitamins. The bile has five main functions:
- Aids in the digestion of fat via fat emulsification.
- Absorption of fat and fat-soluble vitamins.
- Excretion of bilirubin and excess cholesterol.
- Provides an alkaline fluid in the duodenum to neutralize the acidic pH of the chyme that comes from the stomach.
- It provides bactericidal activity against microorganisms present in the ingested food.
In fat metabolism, the liver cells break down fat and produce energy. They also create about 800 to 1,000 ml of bile per day. This yellow, brownish, or olive-green liquid is collected in small ducts and then passed to the central bile duct, which carries the bile to a part of the small intestine called the duodenum.
The liver is one of the largest organs in the body and has many critical metabolic functions. It converts the nutrients in our diets into substances that the body can use, stores these substances, and supplies cells with them when needed. It also takes up toxic substances and converts them into harmless substances or ensures they are released from the body.
Regulation, Detoxification, and Elimination
The liver also breaks down toxic substances like drugs, alcohol, and medicines. It removes them by excreting waste into the blood, which is then cleansed by the kidneys. Waste filtered by the kidneys is then removed from the body through the urine.
Another role of the liver is to ensure a healthy blood sugar level by removing sugar from the blood and storing it as glycogen. When blood sugar levels are low, the liver will convert the glycogen to glucose, adding an energy boost to the bloodstream. When blood sugar levels are high, the liver can remove glucose from the blood as needed to keep the sugar levels constant.
The liver also plays a vital role in protein metabolism. Its cells change amino acids in foods so that they can be used to produce energy or make carbohydrates or fats. A toxic substance called ammonia is a by-product of this process. The liver cells convert ammonia to a much less harmful substance called urea, released into the blood. Urea is then transported to the kidneys and passes out of the body in urine.
The liver produces proteins, some of which are important in blood clotting, with the help of vitamin K. It is also an organ that breaks down old or damaged blood cells.