How an Irritable Gut May Contribute to Anxious Thoughts

An unsettled gut doesn’t only affect digestion—it may also influence how we feel and think.

Many people with gut problems report more frequent anxious thoughts, poor sleep, or low mood. While these may seem like separate issues, growing research suggests they are closely linked. The gut and brain share a constant line of communication. When this balance is disturbed—through gut irritation or inflammation—it may affect how the brain works, too.

In this article, we explore how an irritable gut may play a role in mental health, why these symptoms often appear together, and what steps might help support both the body and mind.

What Is an Irritable Gut?

Understanding the basics of gut-related symptoms

An irritable gut refers to a group of symptoms that affect the digestive system. These can include bloating, cramping, gas, and changes in bowel habits—ranging from loose stools to constipation.

The exact causes aren’t fully understood, but many people with these symptoms report flare-ups triggered by stress, diet, or hormonal changes.¹ While uncomfortable, these symptoms are usually not life-threatening. However, they can significantly impact quality of life—especially when tied to emotional distress.

Gut discomfort tends to come in patterns. Some experience symptoms after meals, while others notice them during emotionally stressful periods. The overlap with mood symptoms has prompted scientists to look more closely at the gut-brain connection.

The Gut-Brain Connection

How your digestive system and brain stay in constant contact

The gut and brain send signals back and forth all day. This link is known as the gut-brain axis. It involves nerves, immune signals, and chemicals called neurotransmitters. One of these is serotonin — often linked to mood — and interestingly, around 90% of serotonin is made in the gut.

When the gut is inflamed or imbalanced, it may send signals that affect how the brain processes stress and emotions. This could explain why users with an irritable gut often report more worry, restlessness, or a low mood.²

In recent studies, researchers found that users with irritable gut symptoms had more activity in brain areas involved  in stress response than those without gut issues.^{3, 4}

Imbalance in Gut Bacteria and Mood Changes

Disrupted gut flora may affect mental well-being

The gut contains a large number of bacteria — called the gut microbiota — which help break down food, support the immune system, and maintain balance in the body. But when these bacteria become disrupted, it can cause bloating, discomfort, and even impact mental health.

Research has shown that users with gut symptoms often have different gut bacteria compared to healthy controls. Several studies have linked these bacterial changes to increased anxious thoughts and depressive states, highlighting the significant role the gut plays in mental health.^{5, 6}

One example of this imbalance is small intestinal bacterial overgrowth (SIBO) — a type of bacterial imbalance which is often seen in people with irritable gut symptoms.⁷ Some users with SIBO report better mood and digestion after targeted therapies, although more high-quality research is still needed in this area.⁸

Stress Makes Gut Symptoms Worse — and Vice Versa

Understanding the gut–stress feedback loop

Stress affects everyone differently, but it tends to make gut issues worse. When you’re under pressure, your body releases stress hormones that slow digestion and increase gut sensitivity. This can lead to stomach pain, irregular bowel movements, or bloating.⁹

In fact, a study found that users with irritable gut symptoms often had worse flare-ups during periods of emotional stress.¹⁰

This can turn into a cycle: the more the gut acts up, the more a person might worry. And the more one worries, the more the gut may become irritated. Recognising this loop is often the first step to managing both.

Practical Ways to Support Gut and Mind Together

Simple steps that can support both physical and mental well-being

The good news is that lifestyle changes aimed at improving gut health may also ease anxious thoughts. While these strategies are not cures, they can support overall well-being:

Focus on Fibre and Variety

Eating more fruits, vegetables, whole grains, and fermented foods can help nourish beneficial gut bacteria. Try to introduce variety gradually if your gut is sensitive.

Mindful Eating

Eating slowly, chewing thoroughly, and avoiding highly processed foods may help reduce gut irritation and support calmer digestion.

Movement and Breathwork

Regular gentle exercise, such as walking or yoga, may improve gut motility and lower stress hormones. Deep breathing and relaxation techniques may stimulate the vagus nerve, which helps regulate both gut and mood.

Quality Sleep

Poor sleep can disturb gut–brain communication. Aim for consistent, restorative sleep by following a regular bedtime routine.

Seek Professional Advice

If your digestive problems or anxious thoughts persist or worsen, speak to a health professional. They can help rule out underlying symptoms and guide you to appropriate therapies.

When to Speak to a Health Professional

When gut or mood symptoms may need medical input

It’s important not to dismiss ongoing gut or mental health symptoms. If you notice unexplained weight loss, blood in your stool, severe pain, or if your low mood or anxious thoughts are interfering significantly with your life, seek medical advice promptly.

Conclusion

The connection between the gut and the mind is powerful and real. An irritable gut doesn’t just affect the body — it can ripple into emotional wellbeing, too. By supporting gut health and being mindful of the signals your body sends, you can take meaningful steps towards both digestive comfort and a calmer, clearer mind.

Medical Disclaimer: This article has been written by a licensed medical professional and is intended for general informational purposes only. It does not substitute for personalised medical advice, diagnosis, or treatment. Readers should always seek the guidance of a qualified healthcare provider with any questions regarding a medical condition or health objectives. Never ignore or delay seeking medical advice based on information presented here.

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References

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7. Takakura W, Pimentel M. Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome – An Update. Frontiers in Psychiatry. 2020 Jul 10;11(11).
8. Chojnacki C, Popławski T, Konrad P, Fila M, Błasiak J, Chojnacki J. Antimicrobial treatment improves tryptophan metabolism and mood of patients with small intestinal bacterial overgrowth. Nutrition & Metabolism. 2022 Sep 27;19(1).
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Last Updated on July 18, 2025