ADHD as
circadian
disorder: crucial
reframe or
distractive
deflection?

Huberman, Brandon Luu, Nicholas Fabiano and the emerging circadian ADHD claim

In November 2024, Andrew Huberman — neuroscientist, Stanford professor, and host of the Huberman Lab podcast — posted to 1.2 million X viewers: “Hosted an expert MD/PhD in ADHD this week. Turns out it may be a circadian disorder, which explains why so many adults now have it […]”

The post went (semi) viral. Comments flooded in celebrating the breakthrough. Finally, an explanation that made sense. ADHD was no longer a cognitive disorder — it was just your body clock being off.

The claim stems from research that has been accumulating, most notably over the last couple of years, and most recently synthesised in a December 2025 paper published in Frontiers in Psychiatry by Brandon Luu (Department of Respirology, Queens University) and Nicholas Fabiano (Department of Psychiatry, University of Ottawa). Their perspective piece, titled “ADHD as a circadian rhythm disorder: evidence and implications for chronotherapy,” argues that circadian rhythm dysfunction represents “a clinically significant and highly prevalent phenotype (meaning an individual’s observable traits) in a substantial subgroup of individuals with ADHD.”

The authors document that 73-78% of people with ADHD have delayed sleep-wake cycles, dim-light melatonin onset delayed by 45-90 minutes in children and 90 minutes in adults, and blunted cortisol rhythms. Sleep disturbances affect up to 80% of adults with ADHD and 82% of children. Biological markers include reduced pineal gland volume and attenuated peripheral clock-gene rhythms (BMAL1/PER2).

Intervention studies show melatonin and bright light therapy can successfully advance circadian phase in ADHD populations. Some data correlate phase advancement with symptom improvement.

Sounds compelling. The narrative is spreading across social media, wellness communities, and clinical circles. ADHD is being reframed as fundamentally a timing disorder.

Except the paper’s own conclusion undermines the viral framing: “evidence on remission of ADHD with circadian interventions is lacking.”

Read that again.

Three-quarters of people with ADHD show circadian disruption. Interventions can shift their phase timing. But those interventions don’t resolve ADHD symptoms.

So what exactly is being discovered, or just reframed here?

What the evidence actually demonstrates

The research Luu and Fabiano recently synthesised documents real phenomena. People with ADHD do show delayed circadian rhythms at rates far higher than the general population. Melatonin onset occurs later. Cortisol peaks are blunted and delayed. Peripheral clock genes show attenuated expression.

But correlation isn’t causation, and the intervention data exposes the gap.

A randomised trial of adults with ADHD gave 0.5mg melatonin nightly. Dim-light melatonin onset advanced by 88 minutes. ADHD symptoms improved by 14%. Another trial in children used 3-6mg melatonin for four weeks. Phase advanced by 44 minutes. Total sleep time increased by 20 minutes. But “there was no identified changes in cognitive performance or problem behaviour” within that period.

Bright light therapy shows similar patterns. Two weeks of 10,000 lux morning exposure advanced melatonin onset by 31 minutes and mid-sleep time by 57 minutes in adults with ADHD. A “significant interaction” appeared between symptom improvement and phase advance — but this was a pilot study with no control group and effect sizes weren’t quantified.

The strongest evidence comes from a behavioural sleep intervention in 244 children with ADHD: two sessions with psychologists providing sleep strategies plus a follow-up call. Six months later, ADHD symptoms, sleep quality, and functioning all improved significantly.

Except here’s the problem: the intervention wasn’t circadian-specific. It was general sleep hygiene, behavioural structure, and parental support. You can’t isolate circadian phase shift as the active mechanism when multiple variables changed simultaneously.

Luu and Fabiano acknowledge these limitations throughout their paper. Circadian disruption is “highly prevalent” but “not universal.” The relationship is “complex and bidirectional.” Intervention effects vary and responder phenotypes remain undefined. Most critically: “evidence on remission of ADHD with circadian interventions is lacking.”

That’s not a paradigm shift. That’s preliminary correlation awaiting mechanistic clarification.

Yet the social media framing — amplified by modern-day neuroscientist’s platform reach — presents it as settled: ADHD is a circadian disorder. The complexity collapses into simple causation. The caveats disappear.

The lived experience clarity: late nights as refuge, not dysfunction

The research measures delayed sleep-wake timing and treats it as pathology requiring correction. But what if late nights aren’t dysfunction — they’re adaptation?

For people with ADHD — especially undiagnosed, unmedicated, or masking through the day — daytime environments are incompatible with their systems. Sensory processing overload while tolerating on the surface. Social performance demands in public. Executive function failures under observation. Constant task-switching. Interruptions. And expectations to maintain neurotypical communication and behaviour patterns despite existing with a neurodivergent operating system.

Night-time offers what daytime denies: quiet, focus, autonomy, absence of prior-pressure, and no social surveillance.

Many people with ADHD don’t avoid early sleep because of melatonin onset alone. They avoid it because late hours are the only time they get uninterrupted solitude and cognitive quiet. The world stops making demands. The performance pressure lifts. The brain can finally operate at its own pace without external interference.

In this sense, staying up late isn’t circadian pathology but basic and adaptive rational refuge.

The circadian research measures the timing shift but doesn’t interrogate what created the need for it. If your brain can only function properly when the world stops demanding performance, the problem isn’t your melatonin onset — it’s the environment that requires you to operate on schedules and in conditions fundamentally incompatible with how your nervous system processes your reality.

Pathologising the adaptation ignores what made it necessary while potentially distracting from underlying need with a reframe.

Calling late-night preference (learned and patterned system behaviour) a “circadian dysfunction” medicalises a long-term behavioural response to day-time environmental mismatch. It positions the individual as disordered (square pegs) rather than addressing the systems that create the conditions (rigid round holes) requiring the adaptation and flexibility in the first place.

Of course, that is not the job of neuroscientists, nor am I claiming that the neuroscientist’s working in this field should even take this into consideration — their job is to synthesise what they are working on, and mine is to do the same, which I would not be able to do in the first place without their breaking of new ground. I am merely providing ontological and contextual analysis after the fact, and it is not designed to take away from the facts they are finding nor discourage their work. On the contrary: highlighting it, and critically analysing it from my own perspective.

The modern-day cross-generation complex causation problem nobody is addressing

Luu and Fabiano’s paper states circadian disruption is “highly prevalent” in ADHD but admits the interaction is “complex and bidirectional.” That’s academic language for: we don’t know which way the arrow points.

Possibility one: ADHD causes circadian disruption. Inattention and impulsivity lead to irregular schedules, poor sleep hygiene, late-night stimulation-seeking, inconsistent routines. And the delayed phase is downstream of the neurodevelopmental condition.

Possibility two: Circadian disruption causes ADHD symptoms. Phase delay impairs executive function, attention regulation, and impulse control. What presents as ADHD is actually sleep deprivation and chronobiological misalignment expressing through behaviour.

Possibility three: Stimulant medications create circadian disruption. Methylphenidate and amphetamines suppress appetite, delay sleep onset, and manipulate dopamine systems that help to regulate circadian rhythms. The “ADHD circadian phenotype” is iatrogenic — meaning created by the treatment, not inherent to the condition in the first place.

Possibility four: Modern environments create both simultaneously. Screen exposure, artificial light, irregular schedules, processed food timing, chronic stress — all documented circadian disruptors — also happen to impair executive function, attention, and impulse regulation. ADHD and circadian dysfunction aren’t causally linked; they’re parallel manifestations of environmental mismatch. This is the “explains why so many adults now have it” that Huberman referred to.

The research can’t distinguish between these. The paper notes that stimulant medication “improves” daytime melatonin suppression but doesn’t address whether years of stimulant use might have created the circadian phenotype now being “discovered.” It documents smaller pineal gland (where melatonin, the hormone that regulates sleep-wake cycles is produced and regulated) volumes in people with ADHD but doesn’t control for medication history.

And nobody’s discussing the complex feedback loop that the modern world has all generations entrenched within.

The brain (ADHD, or not) seeks stimulation to regulate attention > Screens (where, typically, most resort to for their stimulation) provide infinite dopamine hits > Blue light plus stimulation delays melatonin onset > Late sleep causes morning dysfunction > Daytime impairment increases evening refuge-seeking > Repeat.

Is that circadian dysfunction? Or is that what living with ADHD looks like — or, generally, as a human with mammalian systems — in an always-on device-saturated reality when the behaviour becomes biologically embedded and neurally entrenched through deep grooves carved over years of patterning a life normalised with technological and algorithmic infiltration hijacking our mammalian systems? And remember, from the cohort of Generation Z downwards, we have practically all humans (unless you’re Amish, or a handful of other groups that have entirely dodged this timeline) completely native to this world we still don’t respect the myriad implications and dangers of.

The dopaminergic system (what I call the “Messenger of Pursuit” in my book that also gives the name “Messengers” to neurotransmitters) becomes entrained to nocturnal reward patterns. The grooves (neural pathways) deepen, thanks to glutamate (the “Messenger of Ignition”).

Because of this, the routine embeds into one’s nervous system (the actual mammalian system your mind operates from). Especially for younger people or those who don’t understand what they’re messing with regarding technology, social media, and blue light stimulation — the pull becomes harder to resist. They won’t simply “put it down” early or read a book before bed when the dopaminergic hook is that strong and the behavioural grooves are that entrenched.

This isn’t circadian pathology that needs pharmaceutical or supplement correction. It’s environmental capture that requires structural intervention — but that’s much more nuanced and harder to monetise, isn’t it!

The 30+ years old phenomenon and environmental accumulation

I’ve noticed something over the past few years, that might be an uncomfortable read for some: increasing numbers of people in their mid-30s and older are identifying as ADHD for the first time, or attributing symptoms they’ve had for decades to the condition. They tell me about it. Increasingly. Online, and when I’m out and about meeting people in the world and I tell them what I do (so no echo chamber effect). And I am seeing it more and more in all areas of my work.

These aren’t people who were undiagnosed children. They’re people who functioned adequately — or well — for years, then hit a point where executive function collapsed, attention fragmented, and impulsivity or hyperactivity (often internal, not visible) became unmanageable.

And, truthfully, these people are making up a large number of the increased diagnosis numbers that are continually called an “epidemic”. Not just “kids these days”, though they’ve certainly got their own self-diagnosis problem. 

So, what changed? I’d imagine decades of:

1 — Disrupted sleep from unquestioned rigid routines (“that’s the way it’s always been, and the way my parents had to do it!”), work stress, parenting, and caregiving while potentially compromising on their own care for themselves;

2 — Screen habit accumulation and social media adoption, beginning and increasing from first smartphone use, without awareness of biological, neurological and mammalian hijacking in play;

3 — Loss of natural light exposure and autonomous rhythms through office work and commuting;

4 — Irregular eating patterns and caffeine dependence to compensate for fatigue;

5 — Chronic low-grade stress without recovery periods;

6 — Learned behaviour and system dependency over time to drugs, alcohol, smoking, and God knows what else as nervous system down-regulators.

To name a few. And, again, don’t make the mistake of thinking I’m merely punching upwards here, as each point I listed is relevant regardless of one’s age. The point is the accumulation that can lead to the inevitable collapse: whether neurological (“disorder”) or biological (autoimmune, etc), is besides the point.

So is this ADHD? Or is this what modern environmental mismatch looks like when it finally breaks (“normal”) mammalian function after years of accumulation and appropriating normalcy?

The circadian research can’t distinguish between inherent ADHD with secondary circadian effects, and circadian disruption causing ADHD-like symptoms, and environmental factors creating both simultaneously.

If two to three decades of poor sleep, screen exposure, artificial light, and irregular — or regular, but counter to mammalian requirements —  routines produce attention deficits, impulsivity, and executive dysfunction — and those symptoms are proven to resolve over time with the structured intervention of sleep restoration, light hygiene, and routine stabilisation — was that ADHD, or was that just being alive in 2025 and beyond?

Who profits from the reframe

Shock horror: the reframe serves a function here. It medicalises the presentation without requiring anyone to address the environmental and lifestyle causes. You’re not a sick mammal from the conditions you’ve been living under — when it’s more likely you are, to whatever degree, than you are not. Instead, you have a circadian disorder. Here’s some melatonin. Go to bed earlier.

This matters because in my book, I write about exactly this phenomenon — how established habits and patterns (disrupted sleep, lack of self-care, technology and screen use) become linked to both circadian and dopamine system dysfunction. When both systems are compromised simultaneously, the presentation inevitably manifests as ADHD-like symptoms, regardless of whether someone has the underlying neurodevelopmental condition.

So the question isn’t whether circadian disruption contributes to ADHD symptomatology. It clearly does. The question is whether we’re discovering an inherent feature of ADHD, or documenting a bug in the world we built: what happens when modern environments systematically dysregulate basic biological and mammalian rhythms in ways that disproportionately affect people with existing vulnerabilities, but affect all of us nonetheless.

The circadian ADHD hypothesis aligns perfectly with multiple commercial, institutional, and pharmacological (remember the paracetamol/Tylenol/Leucovorin drama?) interests:

Supplement industry — melatonin, magnesium, glycine, and “sleep stacks” marketed for circadian optimisation. Functional medicine practitioners selling protocols for those predisposed to “biohacking”, micro-optimising, and obsessing over health and lifestyle improvements.

Device manufacturers — light therapy boxes, blue-light blocking glasses, sleep trackers, dawn simulation alarms. Entire product categories justified by circadian dysfunction.

Wellness influencers — “optimise your circadian rhythm” becomes evergreen content. Protocols to sell. Courses to teach. Affiliate links to fund.

Medical establishment — non-pharmaceutical intervention that still medicalises the problem. You’re not sick from capitalism, screens, or work schedules, no; you have a timing disorder we can treat behaviourally and if not, you’ve got bad discipline.

Tech companies — deflects from the role of devices, social media, algorithms, and artificial light in creating the dysfunction in the first place. The problem isn’t the phone you turn to without conscious intention. The problem is your melatonin onset. Duh.

Pharmaceutical industry — stimulant manufacturers benefit from Huberman’s “counterintuitive” framing that their drugs help sleep when taken early. Turns a side effect (delayed sleep onset when taken late) into a feature (circadian regulation when timed properly).

Remember: none of this means the research is wrong. It means the reframe serves interests beyond promoting the individual’s capacity for sovereignty, self-awareness, and self-compassion.

Luu and Fabiano propose “a pragmatic, behavioural-first clinical pathway” including routine screening, chronotype assessment, fixed wake times, morning bright light, evening light restriction, and selective low-dose melatonin. None of that is harmful. Much of it will probably help. Regardless of how unreasonable it is for the average person to participate in that intervention-stack, and not withstanding how exhaustive it is to even consider implementing.

But positioning ADHD as primarily a circadian disorder based on correlational evidence and pilot interventions that don’t achieve symptom remission allows everyone to avoid asking harder questions about why so many people — ADHD or not — are living in conditions that dysregulate every biological rhythm we have.

Environmental mismatch vs individual pathology

The multimodal behavioural intervention study cited in Luu and Fabiano’s paper offers the clearest demonstration of what’s actually happening. Thankfully.

Researchers took 22 healthy “night owls” and implemented: wake 2-3 hours earlier, fixed wake time daily, maximise morning light, reduce evening light, no late dinners, no caffeine after 15:00, morning exercise, and no late naps.

Three weeks later, the results: melatonin onset advanced ~2 hours, wake time advanced 1.9 hours, cortisol peak advanced 2.2 hours. Depression scores dropped 58%. Stress dropped 40%. Cognitive and physical performance improved.

This worked in people without ADHD.

The intervention didn’t target a disorder. It targeted environmental misalignment — then measured how quickly biology responded when conditions changed.

If the same protocol works in healthy late chronotypes and people with ADHD, what does that tell you about the aforementioned 30+ phenomena, and what does it say about whether ADHD is “really” a circadian disorder,  or whether modern environments create circadian disruption that everyone experiences, but people with ADHD experience more intensely or with less compensatory capacity?

In my final assessment, calling ADHD a circadian disorder based on the current evidence is premature at best, and is absolutely (though not intentionally: again, not the neuroscientist’s job) a distraction from asking why so many people — ADHD or not — are living in conditions that dysregulate every biological rhythm we have.

If 75% of people with ADHD show circadian disruption, but circadian interventions don’t remit ADHD, then either:

1 —The 75% stat is correlation, not causation;

2 — ADHD symptoms themselves are downstream of something deeper, and both attention difficulties and circadian disruption are manifestations of the same underlying issue;

3 — Modern environments create conditions that break multiple mammalian regulatory systems simultaneously, and we’re pathologising and medicalising adaptive responses to systemic dysfunction.

I’m led to be convinced that, through all that I’ve synthesised thus far, the truth lies in points two and three.

The reframe wants simple causation: ADHD is circadian dysfunction, fix the timing, fix the condition. But the evidence shows: timing is off, interventions can shift it, symptoms sometimes improve, but ADHD doesn’t remit.

Which isn’t a reframe. It’s a correlation awaiting mechanistic understanding — and a convenient narrative for industries that profit from selling individualised fixes instead of addressing environmental causes.

The crucial question isn’t whether circadian disruption matters in ADHD. That’s now proven. The crucial question is: why are we calling ADHD a circadian disorder when the evidence doesn’t support it and on the contrary signals that circadian disorder is prevalent in modern populations generally, and who benefits from that reframe?

It certainly puts the “aren’t we all a bit ADHD?” question and retort to its existence being invalid into a new light, that’s for sure.

Update — May 2026

Five months on, the “environmental mismatch dysregulating multiple mammalian systems simultaneously” reading has only consolidated. The reframe-as-deflection critique has held up — and the parallel evidence has accumulated faster than the circadian-disorder advocates have been able to absorb it.

The Directory’s coverage of social media creating ADHD symptomatology and neurology examined a January 2026 University of Amsterdam study where pre-existing cognitive deficits failed to mediate the relationship between ADHD and problematic social media use — exactly the null result you would expect if symptoms emerge from cumulative environmental exposure rather than endogenous timing dysfunction. The same point made empirically.

Two further pieces sit in the same cluster. Autistic sleep problems as nervous system dysregulation extends the argument across neurotypes — the sleep is downstream of regulation, not the cause of the dysfunction. And technostress as the adult version of cybernetic attention strain traces the formatting through the lifespan, with the same digital infrastructure producing the symptoms it then sells products to manage.

The circadian data is real. The reframe is still premature. And the supplement industry continues to thank Huberman for the assist.

Citations

Frontiers in Psychiatry — ADHD as a circadian rhythm disorder: evidence and implications for chronotherapy (Luu & Fabiano, 2025)

Andrew D. Huberman (@hubermanlab on X) — post on ADHD and circadian dysfunction (November 16, 2024)

Facer-Childs et al. (2019) — Resetting the late timing of ‘night owls’ has a positive impact on mental health and performance

Hiscock et al. (2015) — Impact of a behavioural sleep intervention on symptoms and sleep in children with ADHD

Van Andel et al. (2021) — Effects of chronotherapy on circadian rhythm and ADHD symptoms in adults

Brandon Luu (@BrandonLuuMD on X) — post on latest research paper: “what this means for treatment” (December 16, 2025)

Nicholas Fabiano (@NTFabiano on X) — post on latest research paper: “ADHD is a circadian rhythm disorder” (December 16, 2025)