Researchers tested whether special bacteria called probiotics could help children with ADHD improve their ability to focus and control their behavior. They gave 84 children with ADHD either a probiotic supplement or a fake pill for 2 months. The children who took probiotics showed significant improvements in their ability to pay attention, plan ahead, and manage their impulses compared to those who took the fake pill. While these results are promising, scientists say more research is needed to confirm these findings and understand exactly how probiotics might help the brain.

The Quick Take

  • What they studied: Whether taking probiotic supplements (beneficial bacteria) could help children with ADHD improve their ability to focus, plan, and control their impulses
  • Who participated: 84 children diagnosed with ADHD were split into two groups: one received probiotics daily for 2 months, and the other received a placebo (fake pill) that looked identical
  • Key finding: Children who took probiotics showed meaningful improvements in executive function scores (a measure of focus and self-control) compared to those taking the placebo. The improvement was statistically significant, meaning it’s unlikely to have happened by chance
  • What it means for you: Probiotics may help children with ADHD improve their ability to focus and manage their behavior, but this should not replace standard ADHD treatments. Talk to your child’s doctor before starting any supplement, as more research is still needed

The Research Details

This was a triple-blind randomized controlled trial, which is considered one of the strongest types of research studies. Triple-blind means that the children, their parents, and the researchers didn’t know who was getting the real probiotics and who was getting the placebo until after the study ended. This prevents bias from affecting the results.

The 84 children with ADHD were randomly assigned to receive either a daily probiotic supplement containing three types of beneficial bacteria (Lactobacillus Acidophilus, Bifidobacterium Lactis, and Bifidobacterium Longum) or an identical-looking placebo. Both groups took their assigned supplement once per day for 2 months.

Executive function—the ability to focus, plan, organize, and control impulses—was measured using a parent questionnaire called the BRIEF (Behavior Rating Inventory of Executive Function). Parents answered questions about their child’s behavior before and after the 2-month period. The researchers also accounted for other factors that might affect results, like the child’s age, weight, and IQ.

The triple-blind design is important because it prevents expectations from influencing the results. If parents or researchers knew who was getting the real probiotics, they might unconsciously rate those children’s behavior more favorably. By keeping everyone blinded, the study provides more trustworthy evidence about whether probiotics actually work.

Strengths: This is a well-designed randomized controlled trial with a reasonable sample size and proper blinding. The researchers adjusted for factors that could confuse the results. Limitations: The study only lasted 2 months, so we don’t know if benefits continue longer. The study relied on parent reports rather than objective brain measurements. The journal impact factor is unknown, which makes it harder to assess the publication’s prestige. More research is needed to confirm these findings.

What the Results Show

At the start of the study, both groups had similar executive function scores (around 191 points), showing they were evenly matched. After 2 months, the probiotic group’s scores dropped to about 151 points (lower scores are better on this measure), while the placebo group’s scores stayed around 191 points. This difference was statistically significant, meaning it’s very unlikely to have happened by chance.

The improvement in the probiotic group was substantial—about 40 points on the scale. When researchers adjusted for other factors like age, weight, and IQ that might affect results, the difference remained significant and strong. This suggests that the probiotics themselves, rather than other factors, likely caused the improvement.

The results suggest that probiotics may help children with ADHD improve their ability to focus, plan, organize tasks, and control impulsive behavior. These are all key parts of executive function that are often challenging for children with ADHD.

The study doesn’t report specific secondary findings, but the overall improvement in executive function scores suggests benefits across multiple areas of focus and self-control. The fact that improvements were seen after just 2 months suggests that probiotics may work relatively quickly, though longer studies are needed to confirm this.

This research builds on growing interest in the gut-brain connection. Previous studies have suggested that the bacteria in our digestive system may influence brain function and behavior, but research specifically on probiotics and ADHD in children is still limited. This study provides stronger evidence than many previous studies because of its rigorous design. However, results from a single study should be viewed cautiously until other researchers can replicate the findings.

The study only lasted 2 months, so we don’t know if benefits continue beyond that time or if they fade away. The study relied entirely on parent reports of behavior rather than objective measurements like brain scans or computerized tests. The sample size of 84 children is moderate—larger studies would provide more confidence in the results. We don’t know if these results apply to all children with ADHD or only certain groups. The study doesn’t explain exactly how probiotics might improve executive function. Finally, the journal impact factor is unknown, making it harder to assess the study’s overall credibility.

The Bottom Line

Based on this study, probiotics may be worth discussing with your child’s doctor as a possible additional treatment alongside standard ADHD care—not as a replacement. The evidence is promising but not yet conclusive. If your doctor agrees it’s appropriate, a 2-month trial might help you see if your child responds. Choose probiotic supplements that contain the same strains used in this study (Lactobacillus Acidophilus, Bifidobacterium Lactis, and Bifidobacterium Longum) and ensure they’re from a reputable manufacturer. Confidence level: Moderate—this is one well-designed study, but more research is needed.

This research is most relevant to parents of children with ADHD who are looking for non-medication approaches or ways to enhance existing treatments. It may also interest children’s doctors, pediatric psychiatrists, and ADHD specialists. This study should NOT be used to replace prescribed ADHD medications without medical supervision. People with compromised immune systems should consult their doctor before starting probiotics.

In this study, improvements were seen after 2 months of daily probiotic use. However, individual children may respond differently—some might see benefits sooner, while others might take longer. It’s reasonable to try probiotics for at least 2-3 months before deciding whether they’re helping. Keep track of your child’s focus, organization, and impulse control during this time.

Want to Apply This Research?

  • Track your child’s executive function daily using a simple 1-10 scale rating their ability to focus on homework, follow multi-step instructions, and manage frustration. Record this in the app each evening to see patterns over the 2-month trial period
  • Start a daily probiotic supplement routine at the same time each day (such as with breakfast) and log it in the app. Set reminders to ensure consistency, as the study showed benefits after 2 months of daily use
  • Create a weekly summary view in the app comparing focus, organization, and impulse control scores. After 2 months, review the overall trend to determine if the probiotics are making a noticeable difference for your child. Share these tracked results with your child’s doctor

This research is promising but preliminary. Probiotics should not replace standard ADHD treatments prescribed by your child’s doctor. Always consult with your pediatrician or child psychiatrist before starting any supplement, as probiotics may interact with medications or be inappropriate for certain medical conditions. This study was conducted on a specific group of children and results may not apply to all children with ADHD. The long-term safety and effectiveness of probiotics for ADHD remain unclear and require further research.