I Contain Multitudes: The Microbes Within Us and a Grander View of Life

by Ed Yong

Here is what that might look like. If people have high cholesterol levels, doctors might prescribe drugs called statins, which block a human enzyme that’s involved in creating cholesterol. But Stanley Hazen has shown that gut bacteria make good targets, too. Some of them can transform nutrients like choline and carnitine into a chemical called TMAO, which slows the breakdown of cholesterol.50 As TMAO levels build, so do fatty deposits in our arteries, leading to atherosclerosis – a hardening of arterial walls – and other heart problems. Hazen’s team have now found a chemical that can stop this process by preventing the bacteria from making TMAO – all without harming them. Perhaps this chemical, or something like it, will sit alongside statins in tomorrow’s medicine cabinet: two complementary drugs, one that targets the human half of the symbiosis, and another that nudges the microbial half.