- ADHD is linked to genetics, brain chemicals, and gut health.
- A new study has examined how the gut microbiome could influence the condition.
- The levels of three specific fungi in ADHD patients were different.
- A dys balanced microbiome in the Gut can cause inflammation and contribute to mental illness.
- Researchers are currently researching the relationship between gut health and ADHD.
Around 6 million trusted Sources, or 10% of children aged 3-17 in the US, are diagnosed with attention-deficit/hyperactivity disorder (ADHD).
Many factors, including the balance between bacteria in the gut microbiome, are believed to be responsible for its onset and severity.
Now, a New Research Trusted Source from Taiwan scientists, published on April 5 in the Journal of Child Psychology and Psychiatry, has gone a step further and explored the association between ADHD and gut health.
The researchers focused on the mycobiome – which includes the fungi that live in the Microbiome – and found that certain imbalances were more common in ADHD patients.
What was learn from the study
The researchers used high-throughput sequencers to analyze DNA from stool samples taken from 70 people with ADHD and 35 control subjects.
The researchers found that the levels of some fungi in each group were different. Compared to the control group, those with ADHD had significantly higher amounts of Ascomycota and lower amounts of Basidiomycota.
They were not the only differences. The ADHD group had significantly higher levels of Candida (particularly Candida albicans).
The second part of the study included in vitro tests (performed without a living organism). It was found that Candida Albicans increase the permeability of the gut lining.
Inflammation can be a concern if the gut lining is more absorbent.
The results are important, said Jordan Haworth, a gastrointestinal specialist at the Functional Gut Clinic in Manchester, UK. He was not involve with this research.
He told Healthline, “This is one of the first studies to sequence mycobiome both in healthy people and those with ADHD.”
Gut fungi and inflammation
Dr. Sarah Cooke is a UK general practitioner who specializes in nutrition.
She told Healthline that “multiple factors can affect the types and proportions” of fungi. These include ethnicity and lifestyle, medication, diet, type of diet, and how often one brushes their teeth.
This study found three fungi in ADHD patients at ‘abnormal levels.’ Haworth said that the function of Basidiomycota and Ascomycota needs to be clarified.
He explained that “these fungi are not necessarily novel, but they’re something no one else has really looked into.” There’s not much research on their possible mechanism.
Scientists have much better knowledge of Candida.
Haworth explain, “Candida is a general genus of fungi–and it’s the most commonly detect type of fungi found in human feces.” Candida Albicans is relatively harmless in normal health. If your health is compromise, this yeast can thrive and become more harmful.
Antibiotics and immunosuppressants may deplete the Gut of ‘good bacteria’ and encourage yeast growth. Haworth stated that “it’s not been studied whether ADHD medications disrupt the gut microbiome.”
In vitro, tests have shown that Candida Albicans can contribute to the Gut’s permeability, which can lead to inflammation.
Haworth said that the intestinal barrier is responsible for two important tasks. The first job of the intestinal barrier is to absorb nutrients. The second is to stop unwanted things from the Gut from entering the body, mainly microbes.
He explained that this barrier comprises cells tightly packed together by proteins. When these proteins are damage due to inflammation, the spaces between cells increase.
Haworth said that the gaps in the system allow metabolites to enter the bloodstream and travel to other body sites, causing inflammation.
Cooke said that the gut-brain axis was an important path for transmissions. Gut permeability could affect transmissions between the Gut and the brain.
Previous studiesTrustedSource have shown that an imbalanced gut microbiota may trigger an immune reaction leading to inflammation.
How inflammation can affect ADHD
Sarah Nicole Bostan, Ph.D., a clinical health psychologist at Signos and director of the behavioral change strategy, said it’s not clear exactly how inflammation and ADHD relate.
She told Healthline that “the study of gut brain interactions is still at its infancy in relation to functional impairment caused by mental health symptoms.” “[Although] the relationship has become increasingly recognized,” she said.
Currently, there are several hypotheses about the relationship between ADHD and inflammation.
One example is the protective layer surrounding the brain. Haworth explained that the blood-brain barriers are similar to the ones in the Gut. This prevents unwanted substances from the blood from entering the brain.
He continued: “We know from studies, however, that increased intestinal permeability is closely related to a disruption of the blood-brain-barrier–[although] [we can’t be certain what’s causing] it.”
Haworth said that the kynurenine path is another potential factor. Microbes in the Gut convert tryptophan, an amino acid, into serotonin.
He said that “some pathogenic bacteria, including yeast species do not convert tryptophan to serotonin.” They convert it instead into kynurenine. These can also cross the blood-brain barrier to trigger neuroinflammation.
Haworth said the kynurenine path is more responsive to those with mental health issues such as ADHD or depression.
Cooke also explained that some brain swelling is beneficial. However, prolonged inflammation can have adverse effects.
She said that “Neuroinflammation” (inflammation in the brain) is a primary way to protect the brain from pathogens.
Cooke added, “However if this inflammatory state persists, it can be detrimental to the body and prevent cell renewal.”
Neuroinflammation is thought to a factor in the development of ADHD. It’s also note that many patients with ADHD have an autoimmune or inflammatory condition.
Balancing gut microbiota
Does balancing the Microbiome of the Gut and mycobiome ease ADHD symptoms?
Dr. Raphael Wald is a neuropsychologist with Baptist Health’s Marcus Neuroscience Institute. He told Healthline that he would expect improved ADHD symptoms if the gut microbiome was more balanced.
Bostan stated, “Because diet and the environment are heavily influencing gut microbiome, it follows from this that changing diet or environment will also change gut microbiome and mycobiome composition.”
She continued: “However, it’s unclear to what extent this would affect ADHD symptoms.”
Some studies have shown positive results, but more clinical trials are need.
A healthy and happy gut is essential for physical and mental well-being. Jenna Hope, a UK-registered nutritionist, said there are many ways to rebalance your Gut and nourish its beneficial bacteria and fungi.
She told Healthline:
- A varied plant-based diet is important.
- Foods that contain prebiotics and probiotics include onions, garlic, leeks, and bananas. Yogurt (with live cultures), sourdough, fermented vegetables, and yogurt are good sources.
- Avoiding foods high in sugar
- Replace refined grains with whole grains. Whole grains provide dietary fiber, a food source for beneficial bacteria.
- Managing stress
- Prioritizing sleep
- Exercise in Moderation
Other possible causes of ADHD
Other factors may contribute to the development of ADHD and its severity.
“Onset of any mental health challenge, including ADHD, is often multifactorial–meaning there are multiple pathways which influence development,” said Bostan.
According to Wald, there are three other common factors:
- Genetics
- Anatomy (volume of different brain structures)
- Physiology is the study of how chemical messengers work in the brain.
Wald concluded, “unfortunately, there is no single difference between people with ADHD.”
