Attention Deficit Hyperactivity Disorder (ADHD) is a disorder marked by challenges completing tasks and controlling impulses. ADHD affects kids and adults around the world, and as many as 1 in 20 people in the US. ADHD can affect grades, employment, peer relationships and even life expectancy. People living with ADHD have an increased risk of substance abuse and the cost of living with ADHD can be devastating to families and sufferers.
Currently, the best known treatments are stimulant medications. These can make a dramatic difference in the ability of someone with ADHD to focus and control impulses, but they can come with side effects. Even if medication is chosen as treatment, up to 30% of people do not respond to it, meaning they do not see their symptoms improve. Many people or parents of children who have ADHD search for an Integrative approach to managing symptoms, and there is evidence this approach may yield great results. Finding ways to live well and thrive with ADHD is possible, and it may begin in the GI tract.
Diet and ADHD
ADHD is a complex disease that shows some genetic influence, but also appears to be influenced by environment. In the 1980s, Benjamin Feingold discovered that the diet can have a strong effect on attention. Removing artificial food additives and foods high in salicylates improved the symptoms of ADHD. Since the discovery of the Feingold diet, many other dietary influences have been explored for their impact in ADHD symptoms.
A large review of all of the studies that have been done on diets found that one of the strategies that does seem to be effective at managing ADHD with diet is using a “Few Foods Diet”. This plan expands the Feingold diet to remove allergenic foods along with the chemicals additives and salicylates that are known to aggravate restlessness.
The role of the microbiome
When kids respond positively to a restricted diet, it is not feasible to leave them on that diet long term. Kids would be at risk for nutrient deficiencies that may impact their growth and development. But, progress on a restricted diet does help identify the GI tract as a piece of the puzzle for those kids who see an improvement. From that piece of knowledge, a focus on healing the GI tract for those individuals emerges.
The diet is known to change the microbiome. Whole foods rich in fiber provide natural prebiotics that support a strong population of bifidobacteria in the intestines. Bifidobacteria species create a supportive environment for good bacteria, and a hostile environment for bad bacteria and yeast in the GI tract. In a healthy GI tract, diet is enough to keep this population strong, but in a person living with ADHD who responds well to diet changes, the gut needs an extra boost.
Probiotics and ADHD
Probiotics given to kids living with ADHD help eliminate and prevent regrowth of Candida, a yeast that naturally occurs in the GI tract but which can overgrow when the normal GI flora are out of balance. Candida has been linked to many mental health disorders, including ADHD. A diet very low in sugar and rich in fiber and antioxidants can help remove and prevent yeast overgrowth, but this is tough diet to sustain for kids and families. For children, whose growth depends on a wider diversity of nutrients, a probiotic can help balance the gut bacteria much more quickly.
One small study showed that kids who were supported from birth with Lactobacillus rhamnosus GG were less likely to develop neuropsychiatric disorders, such as ADHD. The difference in bacteria that was found in their stool actually showed that the kids who did not develop neuropsychiatric disorders had more bifidobacteria species than the kids not given Lactobacillus species in a probiotic. This is a great example of how the many strains of bacteria that compose the gut flora work together to support each other in creating a healthy environment.
This result is also a great example of why it is so hard to study the effect of one single intervention on a condition as complex as ADHD. Much more research is needed to learn about the link between gut flora and how probiotics can help people living or at risk of developing ADHD, but it is already clear that the microbiome may have a big influence on brain health and behavior.
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