Are Women More Prone to SIBO? Here’s What Research Shows
SIBO and Gender: It’s More Complex Than a Simple Yes or No If you’ve noticed that many women talk about SIBO (Small Intestinal Bacterial Overgrowth) more often than men, you’re not imagining things — but the reason isn’t as simple as “women just get it more.” While some studies report a higher frequency of SIBO diagnoses in women, the scientific picture is nuanced and likely tied to biology, hormonal factors, and how digestive issues are diagnosed and experienced.
What the Research Says About Gender and SIBO
Some clinical studies and reviews have found that female gender is associated with increased odds of SIBO, especially in people with related conditions like IBS (Irritable Bowel Syndrome). In one meta-analysis, female gender was linked to higher SIBO prevalence among individuals with IBS.
However, large population-level research does not always show a clear gender-based difference when looking broadly at SIBO across all groups — meaning that SIBO itself may not occur exclusively or dramatically more in women across the entire population, but patterns emerge in certain clinical settings.
Why Women Might Appear More Affected
🔹 1. Hormones Influence Gut Function
Women experience regular fluctuations in estrogen and progesterone throughout the menstrual cycle and life stages like pregnancy and menopause. These hormones influence gut motility (movement) — and slower motility can allow bacteria to linger and multiply in the small intestine, creating conditions favorable for SIBO.
🔹 2. Conditions Linked With SIBO Are More Common in Women
Digestive disorders that overlap with SIBO symptoms — like IBS or chronic constipation — are often diagnosed more frequently in women. Because these conditions share symptoms such as bloating, discomfort, or irregular bowel habits, SIBO may be investigated or identified more often.
Females with certain gynecological conditions — most notably endometriosis — have also been shown to have very high rates of SIBO or intestinal methanogen overgrowth (IMO), which can make the association between female health conditions and digestive imbalance more visible.
🔹 3. Hormone-Sensitive Gut Nervous System
Hormonal shifts can affect other aspects of gut-brain communication and immune function, which in turn influence how digestion works. For example, stress and hormone-related changes in the nervous system impact gut motility and can contribute to symptoms that overlap with SIBO.
What Doesn’t Drive the Gender Difference
It’s important to clarify that most population-based studies haven’t definitively proven that women are biologically more susceptible to SIBO overall outside of specific contexts like IBS or hormonal health conditions. Some research finds no strong gender difference in general SIBO prevalence when controlled for other factors.
In other words, while many women are diagnosed with SIBO, this does not automatically mean men are immune or that women universally develop it more — but certain patterns and risk factors make the connection more noticeable.
Bottom Line: Real Patterns, Not Just a Trend
So why do so many women seem to have SIBO?
✔ Hormonal fluctuations influence gut motility and digestion.
✔ Women are more often diagnosed with related digestive conditions like IBS, which overlaps with SIBO.
✔ Certain women’s health issues like endometriosis show very high rates of gut bacterial overgrowth.
All of this makes SIBO more discussed and recognized among women, even if the biological differences aren’t fully established outside of specific patient groups.
Women do appear more frequently in SIBO patient populations — especially in clinical settings involving IBS or hormonal conditions — but it’s not simply that women are “naturally more prone.” Instead, a mix of hormonal influence, overlapping conditions, and how symptoms present and are diagnosed likely explains why SIBO conversations often skew female.