The Many Functions of the Liver

As we continue to learn about the digestive system in class, I continue to be amazed at how important each of our organs actually is. But nothing amazes me more than the liver. I know I talk about the liver all the time, but I came across this list of the liver’s functions in my Anatomy & Physiology textbook and I thought it was worth sharing. Use this as a reminder of how important it is to put healthy, real foods into our bodies so that our liver doesn’t have to work too hard. When the liver is overworked, we are more susceptible to weight gain, sickness, and many other health issues.

Carbohydrate Metabolism: The liver works to maintain a healthy blood sugar level. When blood sugar is low, the liver breaks down glycogen to glucose and releases the glucose into our bloodstream. When blood sugar is high (such as right after we eat a meal), the liver converts glucose to glycogen and triglycerides and helps us store these.

Lipid (Fat) Metabolism: Liver cells store some triglycerides. They also work to break down fatty acids to create energy (ATP). The liver creates lipoproteins, which are responsible for transporting fatty acids, triglycerides and cholesterol to and from body cells. The liver also creates cholesterol (remember, over 80% of our cholesterol is made within the body and only 15-20% actually comes from diet).

Protein Metabolism: Liver cells prepare amino acids (proteins) to be used for energy production.

Processing of Drugs & Hormones: The liver can detoxify certain substances such as alcohol, and it excretes drugs. It also chemically alters or excretes thyroid hormones, estrogens and aldosterone. Any over-the-counter or prescription medications we take must be processed by the liver, as they are foreign to our body.

Synthesis of Bile Salts: The liver creates bile salts, which are transported to the small intestine. Bile salts are necessary for the emulsification and absorption of fats.

Storage: The liver is the primary storage site for vitamins A, B12, D, E, and K, and for the minerals iron and copper. The liver stores these nutrients until they are needed elsewhere in the body.

Phagocytosis: The liver is responsible for killing off aged red blood cells and white blood cells, as well as some bad bacteria in the body.

Activation of Vitamin D: The liver, along with the skin and kidneys, is crucial in the activation of vitamin D. The vitamin D absorbed from the sunshine through one’s skin is inactive, and the liver must be involved in the activation process in order for someone to receive the vitamin D’s benefits.

Are you as impressed as I am with the liver? It’s the second biggest organ we have (the skin is the first), so let’s try to take care of it by reducing things like alcohol, smoking, and medications, and by increasing our intake of fresh, whole foods and plenty of water!