Estrogen, the primary female sex hormone, appears to play a key role in why women experience gut pain more frequently enough and intensely than men, according to a new study in mice.

Why Women’s Guts May Be More Sensitive

Roughly 10% to 15% of people worldwide grapple with irritable bowel syndrome (IBS), but women are diagnosed with the condition up to twice as frequently as men.

  • Researchers discovered a specific pathway involving estrogen that amplifies pain signals in the gut.
  • The effect isn’t directly on cells that produce serotonin, but on rarer cells called L-cells.
  • These findings could lead to more targeted therapies for IBS in women.

For years, the reasons behind this disparity have been a medical mystery. Symptoms of IBS – including pain, constipation, diarrhea, gas, and bloating – can be triggered by stress or certain foods, but the underlying biological differences weren’t clear.Now,a study published Dec. 18 in the journal Science suggests a surprising mechanism at play.

“We’ve long suspected that female hormones play a role in gut pain,but the exact mechanism was unclear,” explained David Julius,a neurophysiologist at the University of California,San Francisco. “our findings show a clear pathway for how estrogen can amplify pain signals.”

How Estrogen Impacts Gut Sensitivity

The research team began by comparing gut pain responses in male and female mice. They recorded nerve activity in response to gut stimulation and observed reactions to mild colon inflation.Both tests revealed that female mice consistently exhibited more sensitive guts. Removing the mice’s ovaries – and thus halting estrogen production – brought their sensitivity levels down to match those of the males. Restoring estrogen to normal levels,however,reversed this effect,bringing back the heightened pain response in the females.

To pinpoint where estrogen exerts its influence, the researchers examined various gut cells. Previous research had led them to suspect enterochromaffin cells, which produce approximately 90% of the body’s serotonin, a chemical messenger involved in activating pain-sensing nerves. Surprisingly, estrogen receptors weren’t found on these cell