Gut microbes keep cholesterol under control: Researchers

Scientists found a new way your body controls fat and cholesterol—with help from tiny bacteria in your gut. Here's how it works, step by step.

What are bile acids and what do they do?

When you eat food, especially something with fat like cheese or butter, your body needs help to break it down. That’s where bile acids come in. Bile acids are made from cholesterol in your liver. They act like soap and help break fat into tiny pieces so your body can absorb it. These acids are stored in a small bag called the gallbladder and released into your gut after you eat.

How do gut microbes help with this?

Most bile acids are used over and over again. But some of them are changed by good bacteria in your gut. These bacteria can turn regular bile acids into new forms, called secondary bile acids. This not only helps with fat digestion but also sends signals to the liver to stop making too many bile acids, helping keep everything in balance.

Some bacteria, like Lactobacillus and Clostridioides, are really good at this job. They turn bile acids into special forms that can even help control blood sugar and cholesterol levels.

New discovery: A special molecule called BA-MYC

Scientists found something new called BA-MYC, which is made when gut bacteria work on bile acids. BA-MYC tells your body to make more bile acids, which helps burn more fat. A protein named vanin1 (VNN1) helps in making BA-MYC, and this only happens when the right gut bacteria are around.

In mice, more BA-MYC meant less fat in the liver—even when the mice were eating a high-cholesterol diet. Also, eating fiber (like the kind found in fruits, veggies, and whole grains) helped increase BA-MYC levels.

What does this mean for you?

Even though this study was in mice, similar things might happen in humans too. That’s why it’s important to keep your gut bacteria happy. You can do this by:

• Eating more fiber-rich foods like fruits, vegetables, and oats
• Including fermented foods like yogurt or pickles
• Taking probiotics (good bacteria) when needed

In short, taking care of your gut microbes can help your body manage cholesterol and fat better. Scientists are excited about using this knowledge to create new ways to fight health problems like fatty liver and diabetes in the future.

References: https://www.nature.com/articles/s41586-024-08379-9

https://pmc.ncbi.nlm.nih.gov/articles/PMC9916144/

https://www.nature.com/articles/s41575-021-00566-7

https://www.nature.com/articles/s41577-024-01057-x#citeas

https://pubmed.ncbi.nlm.nih.gov/38525555/

https://karger.com/mmb/article-abstract/24/1/12/197226/Mechanisms-of-Cholesterol-Lowering-Effects-of