A woman holding an illustration of a female reproductive system, specifically focusing on the fallopian tubes, symbolizing how Small Intestinal Bacterial Overgrowth (SIBO) can impact hormonal balance.

SIBO Affects Hormones

January 07, 20253 min read

How SIBO Affects Hormones: Signs and Solutions

Did you know your gut and hormones are in constant communication? When Small Intestinal Bacterial Overgrowth (SIBO) disrupts this balance, it can have cascading effects on your hormones, leading to issues like fatigue, mood swings, and irregular cycles. Let’s explore how SIBO impacts hormonal health and what you can do to regain balance.🔍

The word 'hormones' written on a board with a stethoscope and eyeglasses in the background, symbolizing a focus on health and medical care related to hormonal balance.

♾️The SIBO-Hormone Connection♾️

SIBO affects hormones by interfering with gut functions essential for their production and regulation:

  1. Estrogen Metabolism: The gut houses the estrobolome, a collection of bacteria that helps metabolize estrogen. SIBO can cause estrogen dominance, which contributes to symptoms like bloating, weight gain, and heavy periods.

  2. Cortisol Dysregulation: Chronic stress and inflammation caused by SIBO can elevate cortisol levels, leading to fatigue, anxiety, and sleep disturbances. While elevated cortisol may also suppress other hormone levels like estrogen and progesterone, it can increase other hormones like insulin, which can lead to blood sugar dysregulation issues with either hyperglycemia or hypoglycemia. With either high blood sugars or low blood sugars, you certainly won't feel your best.

  3. Thyroid and Gut Health: Poor nutrient absorption due to SIBO, particularly iodine and selenium, can impair thyroid function. This leads to hypothyroid-like symptoms, including constipation and low energy.

🔍Signs of Hormonal Imbalances Linked to SIBO🔍

✅Persistent bloating or digestive discomfort 😒

✅Mood changes, including anxiety or depression🤢

✅Irregular menstrual cycles or PMMD (Pre-menstrual Dysphoric Disorder: formerly PMS)

✅Weight gain, particularly in the abdominal area

✅Fatigue or difficulty managing stress.

🤔How to Restore Hormonal Balance🤔

1. Address the Root Cause: SIBO

Treating SIBO is crucial for hormonal balance:

  • Antibiotics or Herbal Antimicrobials: Options like rifaximin or berberine help reduce bacterial overgrowth.💊 As we have discussed in other blog articles, you have to make sure that the antimicrobial matches the type of pathobionts that are at stake. Different pathobionts cause hydrogen SIBO, IMO (or methane-predominant SIBO), and ISO (Intestinal Sulfide Overproduction). Because different pathobionts cause different gases to be overproduced, we have to match the antimicrobial agents to their counterparts that are responsible for each gas.

  • Prokinetics: Medications or natural agents like ginger enhance gut motility and prevent relapse.

  • Dietary Adjustments: A low-fermentation diet limits fermentable carbs that feed harmful bacteria. This is helpful in the initial phases of treatment to lessen symptoms, but remember, this is not a long-term fix, nor should it be a long-term goal to stay on a restrictive diet. With SIBO, the longer you have maintained a restricted diet, the harder the journey back to a robust diet can become.

2. Support Hormone Detoxification

  • Add cruciferous vegetables (like broccoli) and flaxseeds to support estrogen metabolism.🥦 I know, it's a Catch-22, right? Some of the very foods that are going to bloat you the most are crucial to detoxification from your very own hormones, namely estrogens.

  • Incorporate healthy fats (avocado, olive oil) for healthy hormone production.🥑

3. Manage Stress

  • Chronic stress worsens cortisol imbalance. Practices like yoga, meditation, or deep breathing exercises can lower stress levels and improve gut motility. 🍃 Get your adrenals tested! If you don't test, then you're just guessing at what may be wrong with your stress hormones and stress axis. Stress can cause cortisol to be too high, or it can cause it to be too low. And, this isn't something that you can reliably sort out by symptoms alone. So, you know my mantra: Don't guess. Test!

4. Balance Nutrient Levels

  • Supplement with magnesium, B vitamins, and vitamin D to support hormone production. ⚖️


💡Key Takeaways💡

  • SIBO can disrupt estrogen, cortisol, and thyroid hormone regulation, leading to systemic symptoms.

  • Treating SIBO with dietary changes, antimicrobials, and gut motility enhancers is essential for restoring hormonal balance.

  • Lifestyle strategies like stress management, adrenal adaptogens, and nutrient support play a pivotal role in long-term gut and hormonal health.❤️‍🩹

Stay tuned for next week’s article on navigating food sensitivities with SIBO—a must-read for anyone managing dietary triggers!



Michael Arthur MD

Michael Arthur MD is a fully-certified functional medicine doctor, hypnotist, and RTT practitioner. He's on a mission to help and guide people with SIBO back to better health and digestive wellness.

Back to Blog