In a latest research, a Gut Microbiome gene has been identified which is shown to lower blood cholesterol levels.

It is often wondered why many people’s blood cholesterol level do not rise even if they consume heavy fat diets. Although, there are many possible reasons to this, scientists have identified a gene present in a particular group of bacteria that helps in breaking down the plasma cholesterol and be excreted though faeces.

Researchers at Broad Institute and Harvard University have linked a group of bacteria present in Human intestines to lower cholesterol levels in blood.

Cholesterol Mystery

It is not new information that bacteria may be responsible for lowering the blood cholesterol. In the early 1900s scientists knew that a certain bacteria is responsible for breaking down Cholesterol into a compound called coprostanol. This compound is then excreted via faeces. Many further studies have been conducted since then to understand the biology of such bacteria, but it is never fully understood.

Some studies have reported that administering particular bacterial species as probiotics can have cholesterol-lowering effects on the host.

While efforts to understand how gut microbial metabolism of cholesterol affects human serum cholesterol levels span over 100 years, proper biology behind this has remained a problem due to a limited understanding of the gut microbes, genes, and enzymes responsible for coprostanol formation.

To understand the procedure, the researchers tried the back way by studying huge data already available. They analyzed gut microbiomes from 3097 people across United States and sequenced nearly 6 million genes found in those microbiomes.

The research was aimed to study bacterial genes that were present in people with coprostanol and without coprostanol in faeces. Only four genes are identified out of which one gene names as Intestinal Stool Metabolism A (IsmA) was picked up as main gene.

What did they find?

The group discovered that people with IsmA gene gut microbiome excreted 55-75% less cholesterol as compared to people without IsmA gene gut microbiome. This also indicated that people have upto 5.4 increase of metabolized cholesterol as cholestenone. Additionally, the people with IsmA gene microbiome had, on average, cholesterol levels were lower by 0.15 mmol/L(2.7mg/dL) lower than people without any IsmA gene copies in their microbiome.

This average affect on blood cholesterol is clinically higher that done by HMGCR and PCSK9 genes, for which there are FDA approved cholesterol drugs available in market.

With results the researchers are hopeful that new anti-cholesterol therapies could be developed which could include populating the patients gut with IsmA gene enriched bacteria. This kind of therapy may prove more beneficial with minimal side effects and long-lasting effects.

If you are suffering from hypercholesterolemia, maybe you should go for Gut Microbiome sequencing. Gut Microbiome Sequencing is now available by many direct-to-consumer companies. For more information about Gut Microbiome Sequencing, you can read our article Gut Microbiome Test. The gut microbiome test helps you to identify many different microbiome species living in you gut and gives a report about your overall health and susceptibility to different diseases.


Douglas J. Kenny, Damian R. Plichta, Dmitry Shungin, Nitzan Koppel, A. Brantley Hall, Beverly Fu, Ramachandran S. Vasan, Stanley Y. Shaw, Hera Vlamakis, Emily P. Balskus, Ramnik J. Xavier,
Cholesterol Metabolism by Uncultured Human Gut Bacteria Influences Host Cholesterol Level,
Cell Host & Microbe,
Volume 28, Issue 2,
Pages 245-257.e6,
ISSN 1931-3128,


Share this article:

Leave a Reply

Your email address will not be published. Required fields are marked *