June 13, 2025

Study Finds Association Between Childhood ADHD and Poor Dental Health

The Spanish National Health Survey tracks health care outcomes through representative samples of the Spanish population. 

A Spanish research team used survey data to explore the relationship between ADHD symptoms and dental and gum health in a representative sample of 3,402 Spanish children aged 6 to 14.

While previous studies have found associations between ADHD and poor dental health, they have not fully accounted for such important determinants of poor oral health as socioeconomic status, dental hygiene, or diet. 

The team therefore adjusted for sociodemographic factors, lifestyle variables, and oral hygiene behaviors. More specifically, they adjusted for sex, age, social class, parental education, exposure to tobacco smoke, consumption of sweets, consumption of sugary drinks, use of asthma or allergy medication, adequate oral hygiene behavior of children, adherence to regular dental visits, parental adequate oral hygiene behavior, and parental adherence to regular dental visits.

With those adjustments, children with ADHD symptoms had over twice the incidence of dental caries (cavities) as their counterparts without ADHD symptoms.

Tooth extractions and dental restorations also occurred with over 40% greater frequency in children with ADHD symptoms.

Gum bleeding, a sign of gum disease, was more than 60% more common among children with ADHD symptoms than among their non-ADHD peers.

Importantly, excluding children with daily sugar consumption, which left 1,693 children in the sample, made no difference in the outcome for cavities.

Excluding children with poor oral hygiene habits, which left 1,657 children in the sample, those with ADHD had 2.5-fold more caries than their non-ADHD counterparts.

Excluding children of low social class, which left 1,827 children in the sample, those with ADHD had 2.6-fold more caries than their non-ADHD counterparts.

Turning to a different method to address potential confounding factors, the team used nearest-neighbor propensity score matching to create virtual controls. This compared 461 children with ADHD to 461 carefully matched children without ADHD.

This time, children with ADHD symptoms had just under twice the incidence of cavities as their counterparts without ADHD symptoms, but 60% more tooth extractions and about 75% more dental restorations. The difference in gum bleeding became nonsignificant.

Noting that “The increased risk of caries was maintained when the analyses were restricted to middle/high social class families and children with low sugar intake, good oral hygiene behaviors and regular dental visits,” the team concluded, “Children with ADHD symptoms in Spain had worse oral health indicators than those without ADHD symptoms. Our results suggest that the association of ADHD symptoms with caries was independent of socioeconomic level, cariogenic diet, frequency of toothbrushing, and dental visits.”

Lucía Fernández-Arce, José Manuel Martínez-Pérez, Miguel García-Villarino, María Del Mar Fernández-Álvarez, Rubén Martín-Payo, and Alberto Lana, “Symptoms of Attention Deficit Hyperactivity Disorder and Oral Health Problems among Children in Spain,” Caries Research (2025), 59(1):35-45, https://doi.org/10.1159/000541013.

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Exploring Gut Microbiota and Diet in Autism and ADHD: What Does the Research Say?


In recent years, there has been growing interest in understanding the connection between our gut microbiota (the community of microorganisms in our digestive system) and various neurodevelopmental disorders like autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). A new study by Shunya Kurokawa and colleagues dives deeper into this area, comparing dietary diversity and gut microbial diversity among children with ASD, ADHD, their normally-developing siblings, and unrelated volunteer controls. Let's unpack what they found and what it means.

The Study Setup

The researchers recruited children aged 6-12 years diagnosed with ASD and/or ADHD, along with their non-ASD/ADHD siblings and the unrelated non-ASD/ADHD volunteers. The diagnoses were confirmed using standardized assessments like the Autism Diagnostic Observation Schedule-2 (ADOS-2). The study looked at gut microbial diversity using advanced DNA extraction and sequencing techniques, comparing alpha-diversity indices (which reflect the variety and evenness of microbial species within each gut sample) across different groups. They also assessed dietary diversity through standardized questionnaires.

Key Findings

The study included 98 subjects, comprising children with ASD, ADHD, both ASD and ADHD, their non-ASD/ADHD siblings, and the unrelated controls. Here's what they discovered:

Gut Microbial Diversity: The researchers found significant differences in alpha-diversity indices (like Chao 1 and Shannon index) among the groups. Notably, children with ASD had lower gut microbial diversity compared to unrelated neurotypical controls. This suggests disorder-specific differences in gut microbiota, particularly in children with ASD.

Dietary Diversity: Surprisingly, dietary diversity (assessed using the Shannon index) did not differ significantly among the groups. This finding implies that while gut microbial diversity showed disorder-specific patterns, diet diversity itself might not be the primary factor driving these differences.

What Does This Mean?

The study highlights intriguing connections between gut microbiota and neurodevelopmental disorders like ASD and ADHD. The lower gut microbial diversity observed in children with ASD points towards potential links between gut health and the pathophysiology of ASD. Understanding these connections is crucial for developing targeted therapeutic interventions.

Implications and Future Directions

This research underscores the importance of considering gut microbiota in the context of neurodevelopmental disorders. Moving forward, future studies should account for factors like co-occurrence of ASD and ADHD, as well as carefully control for dietary influences. This will help unravel the complex interplay between gut microbiota, diet, and neurodevelopmental disorders, paving the way for innovative treatments and interventions.

In summary, studies like this shed light on the intricate relationship between our gut health, diet, and brain function. By unraveling these connections, researchers are opening new avenues for understanding and potentially treating conditions like ASD and ADHD.

April 9, 2024

Dose-dependent Association Found Between Childhood General Anesthesia and ADHD

Childhood General Anesthesia and Subsequent Diagnoses of ADHD

In December 2016, the U.S. Food and Drug Administration (FDA) warned “that repeated or lengthy use of general anesthetic and sedation drugs during surgeries or procedures in children younger than 3 years or in pregnant women during their third trimester may affect the development of children’s brains.” The FDA adds, “Health care professionals should balance the benefits of appropriate anesthesia against the potential risks, especially for procedures lasting longer than 3 hours or if multiple procedures are required in children under 3 years,” and “Studies in pregnant and young animals have shown that using these drugs for more than 3 hours caused widespread loss of brain nerve cells.”

That raises a concern that such exposure could lead to increased risk of psychiatric disorders, including ADHD.

Noting “There are inconsistent reports regarding the association between general anesthesia and adverse neurodevelopmental and behavioral disorders in children,” a South Korean study team conducted a nationwide population study to explore possible associations through the country’s single-payer health insurance database that covers roughly 97% of all residents.

The team looked at the cohort of all children born in Korea between 2008 and 2009, and followed them until December 31, 2017. They identified 93,717 children in this cohort who during surgery received general anesthesia with endotracheal intubation (a tube inserted down the trachea), and matched them with an equal number of children who were not exposed to general anesthesia.

The team matched the unexposed group with the exposed group by age, sex, birth weight, residential area at birth, and economic status.

They then assessed both groups for subsequent diagnoses of ADHD.

In general, children exposed to general anesthesia were found to have a 40% greater risk of subsequently being diagnosed with ADHD than their unexposed peers.

This effect was found to be dose dependent by several measures:

  • Duration of surgery: two-to-three-hour surgeries were associated with a 50% greater risk of subsequent ADHD, and surgeries of more than three hours with a 60% greater risk.
  • Number of exposures: two exposures were associated with a 54% increased risk, and three or more exposures with a 67% greater risk.
  • Placement in an Intensive Care Unit was associated with a 60% greater risk of ADHD.

All three measures were highly significant.

The authors concluded, “exposure to general anesthesia with ETI [endotracheal intubation] in children is associated with an increased risk of ADHD … We must recognize the possible neurodevelopmental risk resulting from general anesthesia exposure, inform patients and parents regarding this risk, and emphasize the importance of close monitoring of mental health. However, the risk from anesthesia exposure is not superior to the importance of medical procedures. Specific research is needed for the development of safer anesthetic drugs and doses.”

June 20, 2024

What the MAHA Report Gets Right—and Wrong—About ADHD and Children's Health

The U.S. government released a sweeping document titled The MAHA Report: Making Our Children Healthy Again, developed by the President’s “Make America Healthy Again” Commission. Chaired by public figures and physicians with ties to the current administration, the report presents a broad diagnosis of what it calls a national health crisis among children. It cites rising rates of obesity, diabetes, allergies, mental illness, neurodevelopmental disorders, and chronic disease as signs of a generation at risk.

The report's overarching goal is to shift U.S. health policy away from reactive, pharmaceutical-based care and toward prevention, resilience, and long-term well-being. It emphasizes reforming the food system, reducing environmental chemical exposure, addressing lifestyle factors like physical inactivity and screen overuse, and rethinking what it calls the “overmedicalization” of American children.

While some of the report’s arguments are steeped in political rhetoric and controversial claims—particularly around vaccines and mental health diagnoses—others are rooted in well-established public health science. This blog aims to highlight where the MAHA Report gets the science right, especially as it relates to childhood health and ADHD.

Some of the Good Ideas in the MAHA Report:

Although the MAHA Report contains several debatable assertions, it also outlines six key public health priorities that are well-supported by decades of research. If implemented thoughtfully, these recommendations might make a meaningful difference in the health of American children:

Reduce Ultra-Processed Food (UPF) Consumption

UPFs now make up nearly 70% of children’s daily calories. These foods are high in added sugars, refined starches, unhealthy fats, and chemical additives, but low in nutrients. Studies—including a 2019 NIH-controlled feeding study—show that UPFs promote weight gain, overeating, and metabolic dysfunction.  What can help: Tax incentives for fresh food retailers, improved school meals, front-of-pack labeling, and food industry regulation.

Promote Physical Activity and Limiting Sedentary Time

Most American children don’t get the recommended 60 minutes of physical activity per day. This contributes to obesity, cardiovascular risk, and even mental health issues. Physical activity is known to improve attention, mood, sleep, and self-regulation.   What can help: Mandatory daily PE, school recess policies, walkable community infrastructure, and screen-time education.

Addressing Sleep Deprivation

Teens today sleep less than they did a decade ago, in part due to screen use and early school start times. Sleep loss is linked to depression, suicide risk, poor academic performance, and metabolic problems.  What can help: Later school start times, family education about sleep hygiene, and limits on evening screen exposure.

Improving Maternal and Early Childhood Nutrition

The report indirectly supports actions that are backed by strong evidence: encouraging breastfeeding, supporting maternal whole-food diets, and improving infant nutrition. These are known to reduce chronic disease risk later in life.

What MAHA Says About ADHD:

ADHD is one of the most discussed neurodevelopmental disorders in the MAHA Report, but many of its claims about ADHD are misleading, oversimplified, or inconsistent with decades of scientific evidence, much of which is described in the International Consensus Statement on ADHDand other references given below.

✔️ Accurate: ADHD diagnoses are increasing.

This is true. Diagnosis rates have risen over the past two decades, due in part to better recognition, broadened diagnostic criteria, and changes in healthcare access.  Diagnosis rates in some parts of the country are too high, but we don’t know why.  That should be addressed and investigated.  MAHA attributes increasing diagnoses to ‘overmedicalization’.   That is a hypothesis worth testing but not a conclusion we can draw from available data.

❌ Misleading: ADHD is caused by processed food, screen time, or chemical exposures.

These have been associated with ADHD but have not been documented as causes. ADHD is highly heritable, with genetic factors accounting for 70–80% of the risk.   Unlike genetic studies, environmental risk studies are compromised by confounding variables.   There are good reasons to address these issues but doing so is unlikely to reduce diagnostic rates of ADHD. 

❌ Inaccurate: ADHD medications don’t work long-term.

The report criticizes stimulant use but fails to note that ADHD medications are among the most effective psychiatric treatments, especially when consistently used.  They cite the MTA study’s long term outcome study of kids assigned to medication vs. placebo as showing medications don’t work in the long term.  But that comparison is flawed because during the follow-up period, many kids on medication stopped taking them and many on placebo started taking medications.   Many studies document that medications for ADHD protect against many real-world outcomes such as accidental injuries, substance abuse and even premature death.

How the MAHA Report Could Still Help People with ADHD:

Despite the issues discussed above, the MAHA Report can indirectly help children and adults with ADHD by pushing for systemic changes that reduce ultra-processed food consumption, increase physical activity, and motivate better sleep practices.

In other words, you don’t need to reject the diagnosis of ADHD to support broader changes in how we feed, educate, and care for children. A more supportive, less toxic environment benefits everyone—including those with ADHD.

May 28, 2025

Patient-Centered Outcomes Research Institute (PCORI) to Fund Landmark ADHD Medication Study

Today, most treatment guidelines recommend starting ADHD treatment with stimulant medications. These medicines often work quickly and can be very effective, but they do not help every child, and they can have bothersome side effects, such as appetite loss, sleep problems, or mood changes. Families also worry about long-term effects, the possibility of misuse or abuse, as well as the recent nationwide stimulant shortages. Non-stimulant medications are available, but they are usually used only after stimulants have not been effective.

This stimulant-first approach means that many patients who would respond well to a non-stimulant will end up on a stimulant medication anyway. This study addresses this issue by testing two different ways of starting medication treatment for school-age children with attention-deficit/hyperactivity disorder (ADHD). We want to know whether beginning with a non-stimulant medicine can work as well as the  “stimulant-first” approach, which is currently used by most prescribers.

From this study, we hope to learn:

  • Is starting with a non-stimulant medication “good enough” compared with starting with a stimulant?
    In other words, when we look at overall improvement in a child’s daily life, not just ADHD symptoms, does a non-stimulant-first approach perform similarly to a stimulant-first approach?
  • Which children do better with which approach?
    Children with ADHD are very different from one another. Some have anxiety, depression, learning problems, or autism spectrum conditions. We want to know whether certain groups of children benefit more from starting with stimulants, and others from starting with non-stimulants.
  • How do the two strategies compare for side effects, treatment satisfaction, and staying on medication?
    We will compare how often children stop or switch medications because of side effects or lack of benefit, and how satisfied children, parents, and clinicians are with care under each strategy.
  • What are the longer-term outcomes over a year?
    We are interested not only in short-term symptom relief, but also in how children are doing months later in school, at home, with friends, and emotionally.

Our goal is to give families and clinicians clear, practical evidence to support a truly shared decision: “Given this specific child, should we start with a stimulant or a non-stimulant?”

Who will be in the study?

We will enroll about 1,000 children and adolescents, ages 6 to 16, who:

  • Have ADHD and are starting or restarting medication treatment, and
  • Are being treated in everyday pediatric and mental health clinics at large children’s hospitals and health systems across the United States.

We will include children with common co-occurring conditions (such as anxiety, depression, learning or developmental disorders) so that the results reflect the “real-world” children seen in clinics, not just highly selected research volunteers.

How will the treatments be assigned?

This is a randomized comparative effectiveness trial, which means:

  • Each child will be randomly assigned (like flipping a coin) to one of two strategies:


    1. Stimulant-first strategy – the clinician starts treatment with a stimulant medication.
    2. Non-stimulant-first strategy – the clinician starts treatment with a non-stimulant medication.
  • Within the assigned class, the clinician and family still choose the specific medicine and dose, and can adjust treatment as they normally would. This keeps the study as close as possible to real-world practice.
  • The randomization is 1:1, so about half the participants will start with stimulants and half with non-stimulants.

Parents and clinicians will know which type of medicine the child is taking, as in usual care. However, the experts who rate how much each child has improved using our main outcome measure will not be told which treatment strategy the child received. This helps keep their ratings unbiased.

What will participants be asked to do?

Each family will be followed for 12 months. We will collect information at:

  • Baseline (before or just as medication is started)
  • Early follow-up (about weeks 3 and 6)
  • Later follow-up (about 3 months, 6 months, and 12 months)

At these times:

  • Parents will complete questionnaires about ADHD symptoms, behavior, emotions, and daily functioning at home and in the community.
  • Teachers will complete brief forms about the child’s behavior and performance at school.
  • Children and teens (when old enough) will complete age-appropriate questionnaires about their own mood, behavior, and quality of life.
  • A specially trained clinical rater, using all available information but blinded to treatment strategy, will give a global rating of how much the child has improved overall, not just in ADHD symptoms.

We will also track:

  • Medication changes (stopping, switching, or adding medicines)
  • Reasons for any changes (side effects, lack of benefit, or other reasons)
  • Any serious side effects or safety concerns

Data will be entered into a secure, HIPAA-compliant research database. Study staff at each site will work closely with families to make participation as convenient as possible, including offering flexible visit schedules and electronic options for completing forms when feasible.

How will we analyze the results?

Using standard statistical methods, we will:

  • Compare the overall improvement of children in the stimulant-first group versus the non-stimulant-first group after 12 months.
  • Look at differences in side effects, discontinuation rates, and treatment satisfaction between the two strategies.
  • Examine which child characteristics (such as age, sex, co-occurring conditions, and baseline severity) are linked to better results with one strategy versus the other.
  • Analyze long-term outcomes, including functioning at home, school, and with peers, and emotional well-being.

All analyses will follow the “intention-to-treat” principle, meaning we compare children based on the strategy they were originally assigned to, even if their medication is later changed. This mirrors real-world decision-making: once you choose a starting strategy, what tends to happen over time?

Why is this study necessary now?

This study addresses a critical, timely gap in ADHD care:

  • Guidelines are ahead of the evidence.
    Existing guidelines almost always recommend stimulants as the first-line medication, yet careful reviews of the evidence show that direct comparisons of stimulant-first versus non-stimulant-first strategies are limited. We do not have strong data to say that starting with stimulants is clearly superior for all children.
  • Real-world children are more complex than those in past trials.
    Most prior medication trials have excluded children with multiple conditions, serious family stressors, or other complexities that are very common in everyday practice. Our pragmatic, multi-site design will include these children and thus produce findings that are directly relevant to front-line clinicians and families.
  • Families and clinicians are asking for alternatives.
    Parents often express worries about stimulant side effects, long-term use, and stigma. Clinicians would like clearer guidance about when a non-stimulant is a reasonable first choice. At the same time, stimulant shortages and concerns about misuse and diversion have exposed the risks of relying almost entirely on one class of medications.
  • The timing is right to influence practice and policy.
    Our team includes parents, youth advocates, frontline clinicians, and national networks that link major children’s hospitals. These partners have helped shape the study from the beginning and will help interpret and share the results. This means that if starting with non-stimulants is found to be similarly effective and safer or more acceptable for some children, practice patterns and guidelines can change rapidly.

In short, this study is needed now to move ADHD medication decisions beyond “one-size-fits-all.” By rigorously comparing stimulant-first and non-stimulant-first strategies in real-world settings, and by focusing on what matters most to children and families overall functioning, side effects, and long-term well-being, we aim to give patients, parents, and clinicians the information they need to choose the best starting treatment for each child.

This project was conceived by Professor Stephen V. Faraone, PhD (SUNY Upstate Medical University, Department of Psychiatry, Syracuse, NY) and Professor Jeffrey H. Newcorn, MD (Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY).   It will be conducted at nine sites across the USA.

January 2, 2026

Evidence-Based Interventions for ADHD

EBI-ADHD: 

If you live with ADHD, treat ADHD, or write about ADHD, you’ve probably run into the same problem: there’s a ton of research on treatments, but it’s scattered across hundreds of papers that don’t talk to each other.  The EBI-ADHD website fixes that. 

EBI-ADHD (Evidence-Based Interventions for ADHD) is a free, interactive platform that pulls together the best available research on how ADHD treatments work and how safe they are. It’s built for clinicians, people with ADHD and their families, and guideline developers who need clear, comparable information rather than a pile of PDFs. EBI-ADHD Database  The site is powered by 200+ meta-analyses covering 50,000+ participants and more than 30 different interventions.  These include medications, psychological therapies, brain-stimulation approaches, and lifestyle or “complementary” options. 

The heart of the site is an interactive dashboard.  You can: 

  1. Choose an age group: children (6–17), adolescents (13–17), or adults (18+). 
  1. Choose a time frame: results at 12, 26, or 52 weeks. 
  1. Choose whether to explore by intervention (e.g., methylphenidate, CBT, mindfulness, diet, neurofeedback) or by outcome (e.g., ADHD symptoms, functioning, adverse events), depending on what’s available. EBI-ADHD Database 

The dashboard then shows an evidence matrix: a table where each cell is a specific treatment–outcome–time-point combination. Each cell tells you two things at a glance: 

  1. How big the effect is, compared to placebo or another control (large benefit, small benefit, no effect, small negative impact, large negative impact). 
  1. How confident we can be in that result (high, moderate, low, or very low certainty).  

Clicking a cell opens more detail: effect sizes, the underlying meta-analysis, and how the certainty rating was decided. 

EBI-ADHD is not just a curated list of papers. It’s built on a formal umbrella review of ADHD interventions, published in The BMJ in 2025. That review re-analyzed 221 meta-analyses using a standardized statistical pipeline and rating system. 

The platform was co-created with 100+ clinicians and 100+ people with lived ADHD experience from around 30 countries and follows the broader U-REACH framework for turning complex evidence into accessible digital tools.  

Why it Matters 

ADHD is one of the most studied conditions in mental health, yet decisions in everyday practice are still often driven by habit, marketing, or selective reading of the literature. EBI-ADHD offers something different: a transparent, continuously updated map of what we actually know about ADHD treatments and how sure we are about it. 

In short, it’s a tool to move conversations about ADHD care from “I heard this works” to “Here’s what the best current evidence shows, and let’s decide together what matters most for you.” 

Meta-analysis Finds Tenuous Links Between ADHD and Thyroid Hormone Dysregulation

The Background:

Meta-analyses have previously suggested a link between maternal thyroid dysfunction and neurodevelopmental disorders (NDDs) in children, though some studies report no significant difference. Overweight and obesity are more common in children and adolescents with NDDs. Hypothyroidism is often associated with obesity, which may result from reduced energy expenditure or disrupted hormone signaling affecting growth and appetite. These hormone-related parameters could potentially serve as biomarkers for NDDs; however, research findings on these indicators vary. 

The Study:

A Chinese research group recently released a meta-analysis examining the relationship between neurodevelopmental disorders (NDDs) and hormone levels – including thyroid, growth, and appetite hormones – in children and adolescents.  

The analysis included peer-reviewed studies that compared hormone levels – such as thyroid hormones (FT3, FT4, TT3, TT4, TSH, TPO-Ab, or TG-Ab), growth hormones (IGF-1 or IGFBP-3), and appetite-related hormones (leptin, ghrelin, or adiponectin) – in children and adolescents with NDDs like ADHD, against matched healthy controls. To be included, NDD cases had to be first-diagnosis and medication-free, or have stopped medication before testing. Hormone measurements needed to come from blood, urine, or cerebrospinal fluid samples, and all studies were required to provide both means and standard deviations for these measurements. 

Meta-analysis of nine studies encompassing over 5,700 participants reported a medium effect size increase in free triiodothyronine (FT3) in children and adolescents with ADHD relative to healthy controls. There was no indication of publication bias, but variation between individual study outcomes (heterogeneity) was very high. Further analysis showed FT3 was only significantly elevated in the predominantly inattentive form of ADHD (three studies), again with medium effect size, but not in the hyperactive/impulsive and combined forms

Meta-analysis of two studies combining more than 4,800 participants found a small effect size increase in thyroid peroxidase antibody (TPO-Ab) in children and adolescents with ADHD relative to healthy controls. In this case, the two studies had consistent results. Because only two studies were involved, there was no way to evaluate publication bias. 

The remaining thyroid hormone meta-analyses, involving 6 to 18 studies and over 5,000 participants in each instance, found no significant differences in levels between children and adolescents with ADHD and healthy controls

Meta-analyses of six studies with 317 participants and two studies with 192 participants found no significant differences in growth hormone levels between children and adolescents with ADHD and healthy controls. 

Finally, meta-analyses of nine studies with 333 participants, five studies with 311 participants, and three studies with 143 participants found no significant differences in appetite-related hormone levels between children and adolescents with ADHD and healthy controls. 

The Conclusion:

The team concluded that FT3 and TPO-Ab might be useful biomarkers for predicting ADHD in youth. However, since FT3 was only linked to inattentive ADHD, and TPO-Ab’s evidence came from just two studies with small effects, this conclusion may overstate the meta-analysis results. 

Our Take-Away:

Overall, this meta-analysis found only limited evidence that hormone differences are linked to ADHD. One thyroid hormone (FT3) was higher in children with ADHD—mainly in the inattentive presentation—but the findings varied widely across studies. Another marker, TPO-Ab, showed a small increase, but this came from only two studies, making the result less certain. For all other thyroid, growth, and appetite-related hormones, the researchers found no meaningful differences between children with ADHD and those without. While FT3 and TPO-Ab may be worth exploring in future research, the current evidence is not strong enough to consider them reliable biomarkers.

 

December 15, 2025