Bile salt

Bile salts are found naturally in bile which is created and secreted by the liver. Bile acids are created from cholesterol (a type of fat), bile (digestion fluid), and proteins also found in the liver. The purpose of bile salts is to help breakdown and transport lipid compounds out of the intestinal lumen and into the intestinal cells. Some examples of molecules that need bile salts for absorption include cholestrol and fat soluble vitamins.

Bile salts are recycled by the body. In fact, only approximately 5% of the bile salts that are used are excreted. This metabolism of bile salts is called enterohepatic circulation.

Bile Salt Supplementation
Supplementing biles salts has been suggested for those with biliary sludge (build up of bile) but not for individuals who have had their gallbladder removed. Experts at Harvard Health claim that there is no reason to supplement bile salts as long as you have a healthy functioning liver.

There may be reasons to consider supplementing with bile salts if you have high cholestrol or have problems absorbing fat soluble vitamins (A,D,E,K). Note that unnecessary supplementation of bile salts has been known to cause diarrhea-- also known as bile acid malabsorption (BAM). BAM is considered to be a major cause of urgency and loose stool in ~1/3 of those with irritable bowel syndrome (IBS).

Bile Salts and the Immune System
Bile salts are capable of communicating with macrophages (a kind of white blood cell) and facilitating an immune response. Therefore it is possible that those with altered concentrations of bile acids may be at risk for a lack of response to infections.

Other Resources
Dr. Berg with a good explanation of bile salts:

https://youtu.be/wKLiXJqVIY8

A link between polymorphonuclear leukocyteintracellular calcium, plasma insulin, and essentialhypertension

https://bit.ly/2TLu2MP

Reprogramming of pro-inflammatory human macrophages to an anti-inflammatory phenotype by bile acids

https://www.nature.com/articles/s41598-017-18305-x

”The ability to infect and replicate in macrophages is implicated in the pathogenesis of many viruses, such as influenza virus [1], rabies virus [2], and dengue virus [3].”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4774560/

The role of macrophages in influenza A virus infection

https://www.futuremedicine.com/doi/pdf/10.2217/fvl.14.65