The Intriguing Connection Between Gut Health, IBS, and ADHD: What You Need to Know

In recent years, the complex relationship between gut health and brain function has become a hot topic. Once regarded as separate areas of health, mental well-being and digestive health are now understood to be closely connected. One area where this relationship is especially intriguing to me is in the intersection of gut health, and Attention Deficit Hyperactivity Disorder (ADHD).

ADHD and the Gut: What’s the Connection?

The gut and brain communicate through what is called the gut-brain axis, a bi-directional pathway that connects the central nervous system (CNS) with the enteric nervous system (ENS). This connection allows the brain to influence gut functions and vice versa. This is why the gut is sometimes referred to as the “second brain”, due to its own complex network of neurons and its ability to produce neurotransmitters, like serotonin, that regulate mood and cognition.

In recent years, research has increasingly focused on how gut health impacts mental and neurological conditions, including anxiety, depression, and more recently, ADHD. One critical aspect of this relationship is the microbiome—the collection of bacteria, microorganisms and all their combined genetic material that reside in the gut. A balanced gut microbiome is essential for proper digestion, immune system function, and mental health. Disruptions in the gut microbiome can affect mood, attention, and focus, all of which are central to ADHD.

ADHD, is a neurodevelopmental disorder affecting attention, impulse control, and executive function, which up until recently had long been considered a purely neurological condition. However, new research points to a possible connection between ADHD and gut health. The gut-brain axis plays a crucial role in regulating neurotransmitters like dopamine, which is heavily involved in the symptoms of ADHD. Emerging research shows that children and adults with ADHD tend to have an altered gut microbiome, similar to individuals with IBS, and individuals with IBS also often experience higher rates of ADHD. This is thought to be because a disrupted or less diverse microbiome can affect the production of neurotransmitters and inflammatory markers, contributing to both ADHD symptoms and digestive issues. For example, gut dysbiosis—a microbial imbalance—may influence brain inflammation, which is thought to affect attention and behaviour. Some studies also suggest that the gut microbiome of individuals with IBS is less diverse and may be dominated by bacteria that contribute to inflammation.  This also explains why people with IBS frequently experience mood disorders and cognitive challenges, which are also hallmarks of ADHD.

IBS and ADHD: The Role of Diet

Diet plays a significant role in managing both IBS and ADHD, given their connection to gut health. For individuals with IBS, certain foods (e.g., gluten, dairy, spicy foods) can trigger flare-ups. Similarly, some people with ADHD find that their symptoms worsen after consuming foods with artificial additives, refined sugars, or preservatives.

A diet rich in plant-based foods, with prebiotics (which feed healthy gut bacteria) and sometimes probiotic rich foods (live beneficial bacteria) can help regulate the gut microbiome and potentially improve both digestive and cognitive symptoms. A balanced diet with sufficient fibre, healthy fats, and low levels of processed sugars support gut health and brain function.

IBS and ADHD: The Role of Managing Stress

Chronic stress is another factor that can influence both IBS and ADHD. Stress can disrupt gut microbiota and cause inflammation, which in turn may aggravate ADHD symptoms. Since stress management is crucial in both conditions, integrating practices such as mindfulness, yoga, meditation, or exercise into a daily routine can offer benefits for mental and digestive health.

As well as can reducing the intensity and frequency of IBS symptoms, mindfulness practices help improve focus, reduce impulsivity, and decrease hyperactivity, which are common ADHD symptoms. Regular mindfulness meditation can also enhance attention span and emotional regulation. CBT is also an effective therapy for managing emotional regulation and behavioural issues associated with ADHD. It helps individuals develop strategies for dealing with impulsive behaviour and negative thought patterns. CBT has also been found to be effective for managing IBS symptoms, particularly stress-related gastrointestinal issues.

Conclusion: Connecting the Dots Between Gut, IBS, and ADHD

For those managing ADHD, paying attention to gut health—whether by making dietary adjustments that support our microbiome, or addressing symptoms directly could offer a new way to improve focus, mood, and overall well-being. As scientists continue to explore the role of gut health in ADHD, I think we will see a shift towards integrative treatments that consider both the mind and the gut.

Dealing with both ADHD and IBS can be extremely challenging, given the significant impact they both have on people’s day to day life. I offer a holistic approach which integrates evidence-based dietary, lifestyle and mindset changes, focused on teaching tools designed to help reduce your symptoms and improve your overall quality of life. Please reach out if you’re struggling!

 References

1.  Pelsser, L. M., et al. (2011). "Effects of a restricted elimination diet on the behaviour of children with ADHD (INCA study)." The Lancet, 377(9764), 494-503.

2.  Kennedy, P. J., et al. (2016). "Irritable bowel syndrome: a microbiome-gut-brain axis disorder?" World Journal of Gastroenterology, 22(21), 4867–4880.

3.  Cohen, S., Conduit, R., Lockley, S. W., et al. (2021). "The overlap between ADHD and IBS." Journal of Attention Disorders, 25(11), 1585-1593.

4.  Cryan, J. F., & Dinan, T. G. (2012). "Mind-altering microorganisms: the impact of the gut microbiota on brain and behaviour." Nature Reviews Neuroscience, 13(10), 701–712.

5.  Dinan, T. G., et al. (2013). "The gut microbiota in mood and behaviour disorders." Frontiers in Neuroscience, 7, 70.

6.  Turnbaugh, P. J., et al. (2019). "The impact of the gut microbiome on neurodevelopmental disorders." Nature Neuroscience, 22(2), 173-181.