It’s hard to think of bacteria as the good guys when it comes to health, but research increasingly shows that the bugs that live in our gut may have a big influence on our well-being. In a new study, scientists find that these bugs may affect how patients respond to potentially life-saving drugs like statins.
Statin drugs can help lower cholesterol levels and reduce the risk of heart disease and stroke in people who take them. But not every patient benefits from the medications, and doctors didn’t have any good explanations for why.
Now, researchers report in the journal PLoS One that the answer may lie with our gut bacteria. These bugs normally live in our intestines and work to digest and break down the food we eat. But scientists have recently learned that their impact goes even further; they also produce vitamins, assist the immune system and may affect everything from our weight to the way we metabolize drugs.
In the new study of 100 people, researchers found that those whose LDL, or bad cholesterol, dropped the most after taking the statin drug simvastatin (Zocor) for six weeks also had higher levels of three bile acids made by the gut bacteria, compared with those whose LDL didn’t decline as much. The people who did not respond well to simvastatin showed higher levels of five other bile acids made by intestinal flora.
Why the difference drug response? The researchers believe that the five compounds made by the poor responders mimic statins, and therefore compete with the drug in binding to the appropriate cells. So, having too many of these bile acids means that statin molecules can’t get to the liver cells where they would regulate production of cholesterol.
“We found that the benefit of statins could be partly related to the type of bacteria that lives in our guts,” the study’s co-author Rima Kaddurah-Daouk, a professor of psychiatry at Duke University, said in a statement. “The reason we respond differently is not only our genetic makeup, but also our gut microbiome.”
That means that it might be possible to test people before they start taking certain statins to know who will respond and who won’t. Blood tests can detect the bile acids that may compete with simvastatin, so people who show high levels could be steered toward different statins that may better control their cholesterol levels.
There’s also the possibility of altering the landscape of the gut flora by consuming probiotics, in order to promote colonies of bacteria that don’t counteract the effects of statins. Some yogurts and other probiotic foods already attempt to take advantage of this beneficial gut flora to boost well-being in other ways. “We’re at a very early stage of understanding this relationship, but [there's] no doubt that metabolites from bacteria are playing an important role in regulating our systems,” said Kaddurah-Daouk. And possibly helping us to be healthier.