Vitamin B1 May Help Regulate Digestive Health, Study Finds

Your gut's daily rhythm might depend on a vitamin hiding in your morning oatmeal.

Scientists studying the genetics of digestion just uncovered something unexpected. After analyzing DNA from 268,606 people across Europe and East Asia, they found that vitamin B1 (thiamine) plays a key role in regulating bowel movements.

The international research team, led by Professor Mauro D'Amato at CIC bioGUNE in Spain, started with a straightforward question: what genetic factors control how often people go to the bathroom? They identified 21 regions of the human genome linked to bowel frequency, including 10 never reported before.

Many findings confirmed what scientists already suspected. The genes pointed to bile acid regulation, which helps digest fats, and nerve signaling that controls intestinal muscle contractions.

But two genes stood out dramatically. Both SLC35F3 and XPR1 are involved in how the body transports and activates vitamin B1.

The researchers wanted to know if this genetic signal showed up in real life. They examined dietary data from 98,449 UK participants and found that people who ate more thiamine-rich foods had more frequent bowel movements.

Here's where it gets interesting. The relationship between thiamine intake and bowel habits varied based on a person's genetic makeup at those two vitamin B1 genes. People with certain genetic variations responded differently to the same amount of dietary thiamine.

"We used genetics to build a roadmap of biological pathways that set the gut's pace," says Dr. Cristian Diaz-Muñoz, the study's first author. "What stood out was how strongly the data pointed to vitamin B1 metabolism."

The Ripple Effect

This discovery could matter for far more people than you might think. Irritable bowel syndrome affects millions worldwide, and gut motility problems sit at the heart of IBS, constipation, and other common digestive disorders.

The study, published in the medical journal Gut, shows meaningful biological overlap between regular bowel movement patterns and IBS. That connection gives researchers specific pathways to explore in future clinical trials.

"The underlying biology is very hard to pin down," Professor D'Amato explains. "These genetic results highlight specific pathways, especially vitamin B1, as testable leads for the next stage of research."

The findings don't mean everyone should start loading up on B1 supplements tomorrow. Scientists need carefully designed clinical studies to understand how thiamine interventions might help specific groups of people based on their genetic profiles.

But for researchers who've struggled to unlock the mysteries of digestive health, this genetic roadmap offers something invaluable: a clear direction forward for developing better treatments that could ease daily discomfort for millions of people worldwide.