Probiotics & ADHD

ADHD is more common than you might think. Attention deficit hyperactivity disorder (ADHD) affects approximately 3-4% of the adult population and 5% of children. An estimated 2.6 million people in the UK have ADHD. A type of neurological difference, ADHD symptoms can impact an individual’s day-to-day life, with many showing signs of inattention, hyperactivity, and impulsivity.

Currently, a number of different methods are recommended to help manage symptoms. Typically, a combination of strategies is used to help meet each individual’s needs. This can include prescription medication, talking therapy (particularly CBT), ADHD coaching, and lifestyle adjustments (exercise, sleep hygiene, mindfulness, diet, time management techniques). However, recent research suggests that probiotics could be an additional helpful tool in managing symptoms of ADHD.

A 2024 study exploring the impact of probiotics on adult ADHD management sought to look at the connection between the gut and the brain, and how, when that relationship is interrupted or isn’t working quite as it should between the gut microbiota and the central nervous system, it contributes to ADHD symptoms. 

The study aimed to test the effects of a multi-strain probiotic on ADHD symptoms, academic achievements, fingernail cortisol concentrations, gastrointestinal (GI) symptoms, and the quality of sleep in adults. 67 students aged 19-30 took part in the double-blind, randomised control trial over the course of three months. 

Results showed that probiotic intervention decreased hyperactivity, while academic achievement and GI symptoms also improved. Measures of fingernail cortisol levels showed that those with lower levels of cortisol had fewer symptoms of inattention and hyperactivity. Younger participants showed the most benefit from taking probiotics. While probiotics were shown to have a positive effect on adult ADHD management, more research is still needed. 

Cortisol and ADHD

Cortisol (stress hormone) levels play a vital role in how our bodies respond to stress, as well as regulating different bodily functions. Cortisol increases our blood sugar, helps repair tissue, manages blood pressure, inflammation, and our metabolism. Research suggests that those with ADHD can have dysregulated cortisol levels, with some studies showing lower levels than typical, and others showing higher levels. When cortisol levels are high, lowering them can help to improve your body’s response to stress, which can lead to improved sleep, reduced inflammation, and better immune function.

Gut health and the mind-body connection

Our gut microbiomes can have more of an impact on our overall health and well-being than we might realise. Your gut microbiome sends messages to your brain, influencing your immune system function, weight, and digestive issues. Made up of good/beneficial bacteria, potentially harmful bacteria, and bad/pathogenic bacteria, your gut microbiome is fragile and replenishing it with healing foods like fermented foods, protein, and bone broth can help. Improving gut diversity can help to improve your sleep as well as affect your mood. 

What exactly does a probiotic do (and how do you tell if you need one?)

Probiotics can help the good bacteria in your gut. Probiotics are meant to help prevent and treat dysbiosis (an imbalance of beneficial microbes in your microbiome). Different kinds of probiotics can help in different ways. You can get probiotics that you can use as a dietary supplement, or you can try and include more foods that contain probiotics in your diet. 

What foods contain probiotics?

Fermented foods and drinks contain probiotics. This includes: yoghurt, kefir, cottage cheese, kombucha, miso, sauerkraut, kimchi, tempeh, and pickles. Other kinds of aged, unpasteurised cheese like Swiss, Gouda, Gruyere, and Edam can contain probiotics. Find out more about probiotic foods and how you can support healthy bacteria.

Working with a nutritional professional

Nutritional professionals can support you in improving your gut health, help you to learn more about the mind-body connection, and assist you in achieving your goals to make healthier changes to your habits. Find out more about how nutritional therapy can help support you.