April 17, 2025

Why The New York Times’ Essay on ADHD Misses the Mark

This New York Times article, “5 Takeaways from New Research about ADHD”, earns a poor grade for accuracy. Let’s break down their (often misleading and frequently inaccurate) claims about ADHD. 

The Claim: A.D.H.D. is hard to define/ No ADHD Biomarkers exist

The Reality: The claim that ADHD is hard to define “because scientists haven’t found a single biological marker” is misleading at best. While it is true that no biomarker exists, decades of rigorous research using structured clinical interviews and standardized rating scales show that ADHD is reliably diagnosed. Decades of validation research consistently show that ADHD is indeed a biologically-based disorder. One does not need a biomarker to draw that conclusion and recent research about ADHD has not changed that conclusion. 

Additionally, research has in fact confirmed that genetics do play a role in the development of ADHD and several genes associated with ADHD have been identified.  

The Claim: The efficacy of medication wanes over time

The Reality: The article’s statement that medications like Adderall or Ritalin only provide short-term benefits that fade over time is wrong. It relies almost entirely on one study—the Multimodal Treatment Study of ADHD (MTA). In the MTA study, the relative advantage of medication over behavioral treatments diminished after 36 months. This was largely because many patients who had not initially been given medication stopped taking it and many who had only been treated with behavior therapy suddenly began taking medication. The MTA shows that patients frequently switched treatments. It does not overturn other data documenting that these medications are highly effective. Moreover, many longitudinal studies clearly demonstrate sustained benefits of ADHD medications in reducing core symptoms, psychiatric comorbidity, substance abuse, and serious negative outcomes, including accidents, and school dropout rates. A study of nearly 150,000 people with ADHD in Sweden concluded “Among individuals diagnosed with ADHD, medication initiation was associated with significantly lower all-cause mortality, particularly for death due to unnatural causes”. The NY Times’ claim that medications lose their beneficial effects over time ignores compelling evidence to the contrary.

The Claim: Medications don’t help children with ADHD learn 

The Reality: ADHD medications are proven to reliably improve attention, increase time spent on tasks, and reduce disruptive behavior, all critical factors directly linked to better academic performance.The article’s assertion that ADHD medications improve only classroom behavior and do not actually help students learn also oversimplifies and misunderstands the research evidence. While medication alone might not boost IQ or cognitive ability in a direct sense, extensive research confirms significant objective improvements in academic productivity and educational success—contrary to the claim made in the article that the medication’s effect is merely emotional or perceptual, rather than genuinely educational. 

For example, a study of students with ADHD who were using medication intermittingly concluded “Individuals with ADHD had higher scores on the higher education entrance tests during periods they were taking ADHD medication vs non-medicated periods. These findings suggest that ADHD medications may help ameliorate educationally relevant outcomes in individuals with ADHD.”

The Claim: Changing a child’s environment can change his or her symptoms.

The Reality: The Times article asserts that ADHD symptoms are influenced by environmental fluctuations and thus might not have their roots in neurobiology. We have known for many years that the symptoms of ADHD fluctuate with environmental demands. The interpretation of this given by the NY Times is misleading because it confuses symptom variability with underlying causes. Many disorders with well-established biological origins are sensitive to environmental factors, yet their biology remains undisputed. 

For example, hypertension is unquestionably a biologically based condition involving genetic and physiological factors. However, it is also well-known that environmental stressors, dietary

habits, and lifestyle factors can significantly worsen or improve hypertension. Similarly, asthma is biologically rooted in inflammation and airway hyper-reactivity, but environmental triggers such as allergens, pollution, or even emotional stress clearly impact symptom severity. Just as these environmental influences on hypertension or asthma do not negate their biological basis, the responsiveness of ADHD symptoms to environmental fluctuations (e.g., improvements in classroom structure, supportive home life) does not imply that ADHD lacks neurobiological roots. Rather, it underscores that ADHD, like many medical conditions, emerges from the interplay between underlying biological vulnerabilities and environmental influences.

Claim: There is no clear dividing line between those who have A.D.H.D. and those who don’t.

The Reality: This is absolutely and resoundingly false. The article’s suggestion that ADHD diagnosis is arbitrary because ADHD symptoms exist on a continuum rather than as a clear-cut, binary condition is misleading. Although it is true that ADHD symptoms—like inattention, hyperactivity, and impulsivity—do vary continuously across the population, the existence of this continuum does not make the diagnosis arbitrary or invalidate the disorder’s biological basis. Many well-established medical conditions show the same pattern. For instance, hypertension (high blood pressure) and hypercholesterolemia (high cholesterol) both involve measures that are continuously distributed. Blood pressure and cholesterol levels exist along a continuum, yet clear diagnostic thresholds have been carefully established through decades of clinical research. Their continuous distribution does not lead clinicians to question whether these conditions have biological origins or whether diagnosing an individual with hypertension or hypercholesterolemia is arbitrary. Rather, it underscores that clinical decisions and diagnostic thresholds are established using evidence about what levels lead to meaningful impairment or increased risk of negative health outcomes. Similarly, the diagnosis of ADHD has been meticulously defined and refined over many decades using extensive empirical research, structured clinical interviews, and validated rating scales. The diagnostic criteria developed by experts carefully delineate the point at which symptoms become severe enough to cause significant impairment in an individual’s daily functioning. Far from being arbitrary, these thresholds reflect robust scientific evidence that individuals meeting these criteria face increased risks for the serious impairments in life including accidents, suicide and premature death. 

The existence of milder forms of ADHD does not undermine the validity of the diagnosis; rather, it emphasizes the clinical reality that people experience varying degrees of symptom severity.

Moreover, acknowledging variability in severity has always been a core principle in medicine. Clinicians routinely adjust treatments to meet individual patient needs. Not everyone diagnosed with hypertension receives identical medication regimens, nor does everyone with elevated cholesterol get prescribed the same intervention. Similarly, people with ADHD receive personalized treatment plans tailored to the severity of their symptoms, their specific impairments, and their individual circumstances. This personalization is not evidence of arbitrariness; it is precisely how evidence-based medicine is practiced. In sum, the continuous nature of ADHD symptoms is fully compatible with a biologically-based diagnosis that has substantial evidence for validity, and acknowledging symptom variability does not render diagnosis arbitrary or diminish its clinical importance.

In sum, readers seeking a balanced, evidence-based understanding of ADHD deserve clearer, more careful reporting. By overstating diagnostic uncertainty, selectively interpreting research about medication efficacy, and inaccurately portraying the educational benefits of medication, this article presents an overly simplistic, misleading picture of ADHD.

Li L, Zhu N, Zhang L, et al. ADHD Pharmacotherapy and Mortality in Individuals With ADHD. JAMA. 2024;331(10):850–860. doi:10.1001/jama.2024.0851

Lu Y, Sjölander A, Cederlöf M, et al. Association Between Medication Use and Performance on Higher Education Entrance Tests in Individuals With Attention-Deficit/Hyperactivity Disorder. JAMA Psychiatry. 2017;74(8):815–822. doi:10.1001/jamapsychiatry.2017.1472

Related posts

News Tuesday: Fidgeting and ADHD

A recent study delved into the connection between fidgeting and cognitive performance in adults with Attention-Deficit/Hyperactivity Disorder. Recognizing that hyperactivity often manifests as fidgeting, the researchers sought to understand its role in attention and performance during cognitively demanding tasks. They designed a framework to quantify meaningful fidgeting variables using actigraphy devices.

(Note: Actigraphy is a non-invasive method of monitoring human rest/activity cycles. It involves the use of a small, wearable device called an actigraph or actimetry sensor, typically worn on the wrist, similar to a watch. The actigraph records movement data over extended periods, often days to weeks, to track sleep patterns, activity levels, and circadian rhythms. In this study, actigraphy devices were used to measure fidgeting by recording the participants' movements continuously during the cognitive task. This data provided objective, quantitative measures of fidgeting, allowing the researchers to analyze its relationship with attention and task performance.)

The study involved 70 adult participants aged 18-50, all diagnosed with ADHD. Participants underwent a thorough screening process, including clinical interviews and ADHD symptom ratings. The analysis revealed that fidgeting increased during correct trials, particularly in participants with consistent reaction times, suggesting that fidgeting helps sustain attention. Interestingly, fidgeting patterns varied between early and later trials, further highlighting its role in maintaining focus over time.

Additionally, a correlation analysis validated the relevance of the newly defined fidget variables with ADHD symptom severity. This finding suggests that fidgeting may act as a compensatory mechanism for individuals with ADHD, aiding in their ability to maintain attention during tasks requiring cognitive control.

This study provides valuable insights into the role of fidgeting in adults with ADHD, suggesting that it may help sustain attention during challenging cognitive tasks. By introducing and validating new fidget variables, the researchers hope to standardize future quantitative research in this area. Understanding the compensatory role of fidgeting can lead to better management strategies for ADHD, emphasizing the potential benefits of movement for maintaining focus.

July 16, 2024

What is Evidenced-Based Medicine?

What is Evidenced-Based Medicine?

With the growth of the Internet, we are flooded with information about attention deficit hyperactivity disorder from many sources, most of which aim to provide useful and compelling "facts" about the disorder.  But, for the cautious reader, separating fact from opinion can be difficult when writers have not spelled out how they have come to decide that the information they present is factual. 

My blog has several guidelines to reassure readers that the information they read about ADHD is up-to-date and dependable. They are as follows:

Nearly all the information presented is based on peer-reviewed publications in the scientific literature about ADHD. "Peer-reviewed" means that other scientists read the article and made suggestions for changes and approved that it was of sufficient quality for publication. I say "nearly all" because in some cases I've used books or other information published by colleagues who have a reputation for high-quality science.

When expressing certainty about putative facts, I am guided by the principles of evidence-based medicine, which recognizes that the degree to which we can be certain about the truth of scientific statements depends on several features of the scientific papers used to justify the statements, such as the number of studies available and the quality of the individual studies. For example, compare these two types of studies.  One study gives drug X to 10 ADHD patients and reported that 7 improved.  Another gave drug Y to 100 patients and a placebo to 100 other patients and used statistics to show that the rate of improvement was significantly greater in the drug-treated group. The second study is much better and much larger, so we should be more confident in its conclusions. The rules of evidence are fairly complex and can be viewed at the Oxford Center for Evidenced Based Medicine (OCEBM;http://www.cebm.net/).


The evidenced-based approach incorporates two types of information: a) the quality of the evidence and b) the magnitude of the treatment effect. The OCEBM levels of evidence quality are defined as follows (higher numbers are better:

  1. Mechanism-based reasoning.  For example, some data suggest that oxidative stress leads to ADHD, and we know that omega-3 fatty acids reduce oxidative stress. So there is a reasonable mechanism whereby omega-3 therapy might help ADHD people.
  2. Studies of one or a few people without a control group, or studies that compare treated patients to those that were not treated in the past.

Non-randomized, controlled studies.    In these studies, the treatment group is compared to a group that receives a placebo treatment, which is a fake treatment not expected to work.  

  1. Non-randomized means that the comparison might be confounded by having placed different types of patients in the treatment and control groups.
  2. A single randomized trial.  This type of study is not confounded.
  3. Systematic review and meta-analysis of randomized trials. This means that many randomized trials have been completed and someone has combined them to reach a more accurate conclusion.

It is possible to have high-quality evidence proving that a treatment works but the treatment might not work very well. So it is important to consider the magnitude of the treatment effect, also called the "effect size" by statisticians. For ADHD, it is easiest to think about ranking treatments on a ten-point scale. The stimulant medications have a quality rating of 5 and also have the strongest magnitude of effect, about 9 or 10.Omega-3 fatty acid supplementation 'works' with a quality rating of 5, but the score for the magnitude of the effect is only 2, so it doesn't work very well. We have to take into account patient or parent preferences, comorbid conditions, prior response to treatment, and other issues when choosing a treatment for a specific patient, but we can only use an evidence-based approach when deciding which treatments are well-supported as helpful for a disorder.

April 23, 2021

ADHD Increases Risky Decision Making: Evidence from a Meta-Analysis

ADHD Increases Risky Decision Making: Evidence from a Meta-Analysis

Adults with ADHD are more likely to have accidents, drive unsafely, have unsafe sex, and abuse substances. These 'real world' impairments suggest that people with ADHD may be predisposed to making risky decisions. Many studies have attempted to address this, but it is only recently that their results have been aggregated into a systematic review and meta-analysis.  This paper by Dekkers and colleagues reports 37 laboratory studies of risky decision-making that studied a total of 1175 ADHD patients and 1222 controls. In these laboratory tasks, research participants are given a task to complete which requires that they make choices that have varying degrees of risk and reward. Using the results of such experiments, researchers can score the degree to which participants make risky decisions. When Dekkers and colleagues analyzed the 37 studies together, they found substantial evidence that ADHD people are more likely to make risky decisions than people without ADHD. The tendency to make risky decisions was greatest for those who, in addition to having ADHD, also had conduct or oppositional disorders, which both have features that indicate antisocial behavior and aggressiveness. We can not tell from these studies why ADHD patients make risky decisions. One explanation is that it is simply the impulsivity of ADHD people that leads to rash, unwise decisions. Another theory postulates that risky decisions reflect deficits in one's sensitivity to rewards and punishments. If we are very motivated by reward and not aware of or affected by the possibility of punishment, then risky decisions will be common. The studies analyzed in the meta-analysis were not designed to demonstrate a link between risky decision-making in the lab and the real world, risky decisions that lead to accidents, and other outcomes. It is reasonable to hypothesize such a link, which is why clinicians should consider risky decision-making when planning treatments.  If you suspect deficits in this area, it will not change your approach to pharmacologic treatment but, given the potential adverse consequences of risky decisions, you should consider referring such patients to cognitive behavior therapy for adult ADHD as this talk therapy may be able to teach ADHD adults how to cope with their decision-making deficits.

May 25, 2021

Updates on ADHD and Vitamin D

The Background on ADHD and Vitamin D

In a blog published in the early days of The ADHD Evidence Project, we discussed an Iranian study examining the association between Vitamin D levels and ADHD in children. The meta-analysis combined 13 studies for a total of 10,344 participants. The researchers found that youth with ADHD had "modest but significant" lower serum concentrations of 25-hydroxyvitamin D compared to those without ADHD.

They also identified four prospective studies that compared maternal vitamin D levels with the subsequent development of ADHD symptoms in their children. Two of these used maternal serum levels, and two used umbilical cord serum levels. Together, these studies found that low maternal vitamin D levels were associated with a 40% higher risk of ADHD in their children. 

Ultimately, the researchers noted that this result "should be considered with caution" because it was heavily dependent on one of the prospective studies included in the analysis. We concluded our blog by pointing out that further research, including more longitudinal studies, is needed before clinicians should start recommending vitamin D supplementation to ADHD patients. 

Further Research: 

Since publishing that initial blog, several more studies have been published about this association. 

The World Federation of Societies of Biological Psychiatry (WFSBP) and the Canadian Network for Mood and Anxiety Disorders (CANMAT) convened an international task force involving 31 leading academics and clinicians from 15 countries between 2019 and 2021. Their goal was to provide a definitive, evidence-based report to assist clinicians in making decisions around the recommendation of nutraceuticals and phytoceuticals for major psychiatric disorders.

For ADHD, the guidelines found only weak support for micronutrients and vitamin D in treatment. Overall, the task force concluded that nutraceuticals and phytoceuticals currently offer very limited evidence‑based benefit for ADHD management.

Another study published in 2023 systematically assessed the results of previously published studies to examine the associations between maternal vitamin D levels, measured as circulating 25(OH)D levels in pregnancy or at birth, and later offspring psychiatric outcomes. This study found a clear association between maternal vitamin D deficiency and subsequent offspring ADHD. They concluded, “Future studies with larger sample sizes, longer follow-up periods, and prenatal vitamin D assessed at multiple time points are needed.”  To that, I will add that studies of this issue should use genetically informed designs to avoid confounding.

Conclusion:

Taking into account the updated research on the topic, there does seem to be an association between low prenatal vitamin D levels and the risk of subsequent offspring ADHD, but it is too soon to say it is a causal relationship due to the possibility of confounding. There is no high-quality evidence, however, that supplementing with vitamin D will significantly reduce symptoms in current ADHD patients. 

July 28, 2025

What Metabolites Tell Us About ADHD — And What This Means for Diet and Treatment

New research has uncovered important links between certain blood metabolites and ADHD by using a genetic method called Mendelian randomization. This approach leverages natural genetic differences to help identify which metabolites might actually cause changes in ADHD risk, offering stronger clues than traditional observational studies.

Key Metabolic Pathways Involved:

The study found 42 plasma metabolites with a causal relationship to ADHD. Most fall into two major groups:

  • Amino acid metabolites from protein metabolism, including those related to tyrosine, methionine, cysteine, and taurine.

  • Fatty acids, especially long-chain polyunsaturated fatty acids (PUFAs) like DHA and EPA, important for brain function.

What Does This Mean for Diet and ADHD?

Since many metabolites come from dietary sources like proteins and fats this supports the idea that diet could influence metabolic pathways involved in ADHD. However, because the study focused on genetic influences on metabolite levels, it doesn’t directly prove that dietary changes will have the same effects.

Notable Metabolites:

  • 3-Methoxytyramine sulfate (MTS): linked to dopamine metabolism, higher genetic levels of MTS were associated with a lower risk of ADHD. Dopamine plays a crucial role in attention and behavior.

  • DHA and EPA: Omega-3 fatty acids abundant in the brain; higher levels were linked to reduced ADHD risk, supporting existing research on omega-3 supplements.

  • N-acetylneuraminate: Involved in brain development and immune function, with higher levels linked to increased ADHD risk, though more research is needed to understand this.

Five metabolites showed bidirectional links with ADHD, meaning genetic risk for ADHD also affects their levels which suggests a complex interaction between brain function and metabolism.

Twelve ADHD-related metabolites are targets of existing drugs or supplements, including:

  • Acetylcysteine: an antioxidant used in various treatments.

  • DHA supplements: widely used to support brain and heart health.

What This Study Doesn’t Show

While these findings highlight biological pathways, they don’t prove that changing diet will directly alter ADHD symptoms. Metabolite levels are shaped by genetics plus environment, lifestyle, and health factors, which require further study.

Conclusion: 

This research provides stronger evidence of metabolic pathways involved in ADHD and points to new possibilities for diagnosis and treatment. Future work could explore how diet or drugs might safely adjust these metabolites to help manage ADHD.

While this study strengthens the link between amino acid and fatty acid metabolism and ADHD risk, suggesting that diet could play a role, ultimately more research is still needed before experts could use this research to give specific nutritional advice.

July 21, 2025

Network Meta-analysis Explores Long-term Efficacy of Nonpharmacological Treatments for Improving Inhibitory Control in Children and Adolescents with ADHD

Background Info:

Executive functions include inhibitory control, working memory, and cognitive flexibility. Inhibitory control is the ability to suppress distractions and focus on goals, which is the main deficit in ADHD. 

Children and adolescents with ADHD often have off-task, unrelated thoughts and are easily distracted, limiting their sustained attention. This makes it difficult for them to focus on tasks and leads to impulsive behaviors that affect their daily life, academics, and social interactions. Improving inhibitory control in ADHD children and adolescents is essential. 

Stimulant medications are commonly used to treat ADHD. However, side effects like insomnia, loss of appetite, and headaches may make parents hesitant to use these medications for their children. 

Non-pharmacological treatments like cognitive training, behavior therapy, and physical exercise have gained attention for their lack of side effects. Research shows that some non-pharmacological methods can improve cognitive outcomes significantly, underscoring their potential in treating ADHD. 

Study:

A Chinese research team identified four key gaps in current research on non-pharmacological treatments for inhibitory control in children with ADHD: 

  • Existing meta-analyses seldom differentiate between short-term and long-term interventions.  
  • Most studies focus primarily on short-term effects and neglect evaluation of maintenance effects through follow-up assessments.  
  • New treatment methods, such as meditation and board games, have not been systematically assessed in meta-analyses for their impact on inhibitory control in children and adolescents with ADHD, leaving their effectiveness uncertain.  
  • Traditional meta-analysis does not tell us which intervention is most effective. Without this comparative analysis, it is difficult to rank efficacy. 

The team therefore performed a network meta-analysis of long-term randomized controlled trials (RCTs) to assess and rank the effectiveness of various non-pharmacological treatments on inhibitory control in children and adolescents with ADHD. 

The team included only RCTs relying on professional diagnoses of ADHD, excluding those based only on parent and teacher rating scales.  

The included studies measured inhibitory control using objective neurocognitive tasks, such as the Stroop test and the Go/No-Go test, to reduce potential subjective bias. Studies relying on parent- or teacher-reported questionnaires were excluded. 

Controls either received no intervention or placebo, such as watching running videos and attending history classes. 

Meta-analysis of 16 studies combining 546 participants found large short-term effect size improvements in inhibitory control from physical exercise. But the two studies with a total of 110 participants that performed a follow-up test reported only a small-to-medium effect size improvement. 

For cognitive training, a meta-analysis of fifteen studies totaling 674 participants reported a medium effect size of short-term improvement in inhibitory control. The ten studies with 563 participants that performed a follow-up test found only a small effect size improvement since treatment initiation. 

For behavioral therapy, meta-analysis of six studies encompassing 244 individuals likewise found a medium effect size short-term improvement in inhibitory control. In this case, however two studies combining 91 participants that performed a follow-up test reported that the medium effect size improvement was maintained. 

For neurofeedback, meta-analysis of seven studies encompassing 186 individuals found a small-to-medium effect size short-term improvement in inhibitory control. The only study that performed a follow-up test reported a small effect size improvement since treatment initiation. 

The two studies with a combined 44 individuals exploring board games found no significant improvement in inhibitory control. Likewise, the two studies combining 32 participants that explored meditation found no significant improvement in inhibitory control. 

There was no indication of publication bias. 

Conclusion:

The team concluded, “Existing evidence shows that physical exercise, behavior therapy, cognitive training, and neurofeedback can effectively improve the inhibitory control of children and adolescents with ADHD. However, meditation, EMG feedback, and board games did not significantly affect inhibitory control. Physical exercise has the best effect among all non-pharmacological treatments, but its impact will be weakened after intervention. Behavior therapy and cognitive training had a slightly lower effect, but they have a better maintenance effect.” 

Ultimately, the study results suggest that non-drug treatments can help children and teens with ADHD improve their ability to control their actions and stay focused. Some methods, like physical exercise, work well at first but may fade once the activity stops. Other methods, like behavioral therapy and cognitive training, may take a little longer to show results but can last longer and make a bigger difference over time. Ultimately, and most importantly, because this work did not study the symptoms of ADHD or its real-world impairments, it provides no reason to change current treatment practices for ADHD.

July 16, 2025