Study Indicates ADHD By Itself Has Negligible Effect on Risk of Type 2 Diabetes

Noting that “evidence on the association between ADHD and a physical condition associated with obesity, namely type 2 diabetes mellitus (T2D), is sparse and has not been meta-analysed yet,” a European study team performed a systematic search of the peer-reviewed medical literature followed by a meta-analysis, and then a nationwide population study.

Unlike type 1 diabetes, which is an auto-immune disease, type 2 diabetes is believed to be primarily related to lifestyle, associated with insufficient exercise, overconsumption of highly processed foods, and especially with large amounts of refined sugar. This leads to insulin resistance and excessively high blood glucose levels that damage the body and greatly lower life expectancy.

Because difficulty with impulse control is a symptom of ADHD, one might hypothesize that individuals with ADHD would be more likely to develop type-2 diabetes. 

The meta-analysis of four cohort studies encompassing more than 5.7 million persons of all ages spread over three continents (in the U.S., Taiwan, and Sweden) seemed to point in that direction. It found that individuals with ADHD had more than twice the odds of developing type 2 diabetes than normally developing peers. There was no sign of publication bias, but between-study variability (heterogeneity) was moderately high.

The nationwide population study of over 4.2 million Swedish adults came up with the same result when adjusting only for sex and birth year. 

Within the Swedish cohort there were 1.3 million families with at least two full siblings. Comparisons among siblings with and without ADHD again showed those with ADHD having more than twice the odds of developing type 2 diabetes. That indicated there was little in the way of familial confounding.

However, further adjusting for education, psychiatric comorbidity, and antipsychotic drugs dropped those higher odds among those with ADHD in the overall population to negligible (13% higher) and barely significant levels. 

The drops were particularly pronounced for psychiatric comorbidities, especially anxiety, depression, and substance use disorders, all of which had equal impacts.

The authors concluded, “This study revealed a significant association between ADHD and T2D [type 2 diabetes] that was largely due to psychiatric comorbidities, in particular SUD [substance use disorders], depression, and anxiety. Our findings suggest that clinicians need to be aware of the increased risk of developing T2D in individuals with ADHD and that psychiatric comorbidities may be the main driver of this association. Appropriate identification and treatment of these psychiatric comorbidities may reduce the risk for developing T2D in ADHD, together with efforts to intervene on other modifiable T2D risk factors (e.g., unhealthy lifestyle habits and use of antipsychotics, which are common in ADHD), and to devise individual programs to increase physical activity. Considering the significant economic burden of ADHD and T2D, a better understanding of this relationship is essential for targeted interventions or prevention programs with the potential for a positive impact on both public health and the lives of persons living with ADHD.”

Miguel Garcia-Argibay, Lin Li, Ebba Du Rietz, Le Zhang, Honghui Yao, Johan Jendle, Josep A. Ramos-Quiroga, Marta Ribasés, Zheng Chang, Isabell Brikell, Samuele Cortese, Henrik Larsson, “In utero exposure to ADHD medication and long-term offspring outcomes,” Neuroscience and Biobehavioral Reviews (2023), 147:105076, https://doi.org/10.1016/j.neubiorev.2023.105076.

Related posts

Nationwide population study finds cancer survivors have much higher risk of ADHD

Nationwide Population Study Finds Cancer Survivors Have Much Higher Risk of ADHD

Thanks to improvements in cancer treatment, there is a growing population of childhood and adolescent cancer survivors (CACSs). CACSs are at an increased risk of chronic physical, psychological, and social problems because of their cancer experiences and intensive cancer treatments. These include depression, anxiety, suicidal ideation, and post-traumatic stress disorder (PTSD). 

To what extent, if at all, does this also apply to ADHD? Noting that “previous studies … have reported inconsistent findings,” a local research team took advantage of Taiwan’s mandatory single-payer National Health Insurance that covers over 99% of the island’s population. More specifically, the National Health Insurance Research Database (NHIRD) maintains data on the insured population available on formal request for study purposes.

Linking the catastrophic illness database, mental disorders database, and longitudinal health insurance database, they tracked children age younger than 10 years and adolescents aged 11-17 years who were diagnosed with any malignancy (cancer) between 2002 and 2011 with no history of major psychiatric disorders (including ADHD). Parental history of major psychiatric disorders was likewise controlled as a potential confounder.

The team identified 5,121 CACSs, which they matched one to ten with 51,210 age-, sex-, income-, and residence-matched cancer-free controls.

ADHD diagnoses were made by board-certified psychiatrists during the study follow-up period (from enrollment through 2011) based on a comprehensive clinical interview and clinical judgment. 

Cancer survivors were diagnosed with ADHD at more than six times the rate of matched controls. Survival duration made no significant difference in this outcome. 

Cancers of bone, connective tissue, skin, and breast were associated with a more than threefold increase in risk of an ADHD diagnosis. For cancers of the circulatory system, there was a more than sixfold increased risk of ADHD, and for those of the genitourinary organs, more than sevenfold increased risk. 

For brain cancer survivors, the increased risk of ADHD was more than twelvefold. That may be at least in part because the brain itself was targeted for treatment in these instances, which plausibly could cause damage resulting in psychiatric disorders.

The team concluded, “we observed a comparatively higher risk of MPDs [major psychiatric disorders] among CACSs than among controls and likewise found that such risks varied across different cancer types. Survivors of both CNS [central nervous system] and non-CNS cancers have increased risks of MPD diagnoses. Among the enrolled CACSs, ASD [autism spectrum disorder] and ADHD were associated with most types/categories of cancers. Long-term care of this vulnerable population must include psychosocial interventions for patients and their families. Physicians need to be aware of early signs of mental health problems in this high-risk subpopulation and arrange early interventions accordingly.”

February 9, 2024

What is The Pharmaceutical Supply Chain? Addressing The ADHD Medication Shortage

The persistent shortage of ADHD medications has been more than a simple annoyance for patients at the pharmacy; the inconsistent availability of these medications has had deep impacts on the daily lives of those struggling without them. While public discourse has pointed fingers at over-prescribing or at restrictive DEA quotas, a recent economic evaluation in JAMA Health Forum suggests we’ve been looking in the wrong direction for an answer to what is causing this. 

The reality of the shortage is less about increased demand and more about a fragile, globalized supply chain that snapped at a critical link. 

Debunking the "Quota Myth":

The prevailing narrative suggested that the Drug Enforcement Administration (DEA) was stifling production by refusing to raise quotas. However, the data tells a different story. In 2022, manufacturers collectively met only about 70% of their allotted production quotas. 

So we know that the problem wasn't that this DEA quota ceiling was too low. In fact, most manufacturers couldn't even reach it. Even when accounting for exports and domestic retail, production remained significantly below the legal limit. Even if the DEA had doubled its quotas, these medications still likely wouldn't have magically appeared on pharmacy shelves. 

The most striking finding in the study is the correlation between the shortage and a sharp decline in the import of raw Active Pharmaceutical Ingredients (APIs).  For the past decade, Germany has accounted for over 85% of US amphetamine imports. In 2022, these imports dropped by approximately 36.7%.  When the API doesn't arrive at the factory, production for medium and small manufacturers grinds to a halt. Unlike larger pharmaceutical giants, these smaller players often lack the inventory cushion or flexibility to quickly pivot to a new supplier. 

When the primary supply of amphetamine-based stimulants (like Adderall) faltered, it triggered a secondary crisis. Patients and clinicians, seeking alternatives, shifted toward lisdexamfetamine (Vyvanse) and methylphenidate (Ritalin/Concerta). 

  • Substitution Strain: This sudden migration of millions of patients created a domino effect, eventually leading to shortages in those medications as well. 
  • The Tolerance Gap: As any clinician knows, these stimulants are not perfect substitutes. Switching a stabilized patient to a different class of medication often leads to a trial-and-error period that may be characterized by poor tolerability or reduced efficacy. 

If we view this shortage purely through a regulatory or clinical lens, we miss the underlying cause of the crisis. The pharmaceutical industry has become a victim of its reliance on "just-in-time manufacturing” and highly concentrated sourcing.  Because over 30% of APIs for the US market are produced in just one or two facilities globally, the system isn't just inefficient; it’s brittle. We are, in a sense, trapped in a system that prioritizes cost-reduction over the resilience required for public health. 

The researchers suggest several policy shifts to prevent a repeat of this supply chain failure: 

  1. Increased Transparency: The FDA should require manufacturers to disclose their specific API suppliers. 
  1. Risk Assessment: Identifying "vulnerable" drugs that rely on fewer than three production facilities worldwide. 
  1. Regulatory Flexibility: Streamlining the process for manufacturers to switch API suppliers during a documented national shortage. 

The ADHD medication shortage wasn't a failure of clinical oversight or a sudden surge in "TikTok-driven diagnoses”, as many have suggested. It was a failure of logistics. It reminds us that the path from a lab in Germany to a patient's hand in the US is far more precarious than we realized. 

July 6, 2026

Brain Stimulation Therapy Shows No Benefit for ADHD in New Meta-analysis

ADHD is a neurodevelopmental condition rooted in delayed or atypical maturation of the prefrontal cortex  (the brain region that governs self-regulation). This maturational lag underlies the hallmark difficulties with attention, hyperactivity, and impulsivity, and also impairs what researchers call executive function: the cognitive toolkit we rely on for working memory, impulse control, mental flexibility, emotional regulation, and the ability to tolerate delays in reward. 

The Background:

Standard treatments work through two main routes. Stimulant and non-stimulant medications are considered very safe and effective treatments, but are not without risk of side effects and are not appropriate for every ADHD patient. Behavioral and psychosocial interventions can improve self-regulation and social functioning, but they require sustained effort and produce variable results. These limitations have kept the search for better alternatives active. 

One candidate that has drawn growing attention is transcranial direct current stimulation (tDCS). The technique is appealingly simple: a weak electrical current is applied to the scalp through small electrodes, modulating the excitability of neurons in the underlying cortex without requiring surgery, anesthesia, or significant discomfort. Its safety profile and ease of use have made it attractive to researchers. 

The Study: 

A newly published meta-analysis set out to give the technique its most rigorous test yet, pooling results from randomized controlled trials, including crossover designs, that compared active tDCS against sham stimulation in people with ADHD across all age groups. 

The Results: 

The findings were consistently null. Across seven trials enrolling 303 participants, tDCS produced no significant reduction in overall ADHD symptom severity compared with sham. Breaking symptoms into their components made no difference: neither hyperactivity/impulsivity nor inattention improved. Turning to executive function, 18 studies with 872 participants found no meaningful gain in inhibitory control, and 12 studies with 506 participants found the same for working memory. Smaller bodies of evidence, including three studies on cognitive flexibility (122 participants) and two on hot executive function, the motivational and emotional dimension of self-regulation (86 participants),  similarly came up empty. Variation in outcomes across studies was small to moderate, and there was no evidence of publication bias skewing the picture. 

The authors’ conclusion was succinct: tDCS was well tolerated but “did not demonstrate significant overall efficacy for core ADHD symptoms or executive functions.” 

July 2, 2026

Children and Adolescents with ADHD Face Significantly Higher Risk of Disordered Eating, Large U.S. Study Finds

Disordered eating (a broad category of persistent, harmful patterns in eating or weight control) affects between 5% and 22% of children and adolescents worldwide, with similar rates seen in the United States. The consequences are far-reaching: these conditions are linked to bone fractures, anemia, malnutrition, dental erosion, obesity, diabetes, hypertension, and elevated cholesterol and triglycerides. They also carry one of the highest mortality rates of any psychiatric illness. 

Eating disorders rarely occur in isolation. They frequently arise alongside other psychiatric and neurological conditions. Yet, until now, no large-scale study had examined these co-occurrences in a nationally representative U.S. sample. A new study addresses that gap, focusing on children and adolescents aged 6–17 and the conditions most commonly associated with disordered eating, including ADHD. 

The Study: 

Researchers drew on data from the 2022–2023 National Survey of Children's Health (NSCH), a nationally representative, cross-sectional survey covering all 50 states and Washington, D.C. Households were selected using stratified, address-based sampling, and parents or guardians completed surveys about one randomly selected child per household. The final sample included 68,000 children and adolescents. 

Results: 

After accounting for factors including sex, age, race and ethnicity, household income, educational attainment, insurance status, and household language, children and adolescents with ADHD were 2.6 times more likely to have some form of disordered eating compared to their typically developing peers. 

The elevated risk appeared across a range of specific behaviors: 

  • 60% more likely to over-exercise 
  • Twice as likely to experience a fear of vomiting or choking 
  • 2.4 times more likely to be extremely selective eaters, to skip meals, or to fast 
  • 2.7 times more likely to purge food or vomit 
  • 3 times more likely to show little interest in food 
  • 3.2 times more likely to binge eat 

A greater tendency toward using diet pills, laxatives, or diuretics was also observed in the ADHD group, though this finding did not reach statistical significance. 

The Take-Away: 

These findings underscore a need to improve both prevention and treatment strategies for disordered eating, particularly in children and adolescents who have ADHD. Clinicians working with this population are advised to screen for a wide spectrum of disordered eating behaviors.