What causes ADHD? (And is it something you did?)
Almost every parent asks it quietly at some point, usually at night, usually after a hard day: did I cause this?
There is a question most parents don't say out loud. It shows up late, after the shouting is over and the house is finally quiet.
Did I do this?
Maybe you think about the screen time you allowed. The snacks. The year things were hard at home. The times you lost your patience. Somewhere in that list, you decide, is the reason your child's brain works the way it does.
It's worth saying plainly: that is not what the research describes.
Why this happens: ADHD runs strongly in families
If you want one fact to hold onto, it's this one. ADHD is one of the most heritable conditions studied in child psychiatry.
In a 2019 review in Molecular Psychiatry, Stephen Faraone and Henrik Larsson brought together decades of twin and family research. Twin studies place the heritability of ADHD at around 74%. That means most of the difference between children who have ADHD traits and children who don't tracks back to inherited biology, not to how they were raised.
This is also why so many parents recognise themselves halfway through a pediatrician's description. Plenty of adults are first told about their own ADHD while sitting in a chair meant for their child.
No single gene is responsible. The same review describes many common genetic variants, each small on its own, adding up across a child's development.
Is it something about how the brain develops?
In their 2016 review in The Lancet, Anita Thapar and Miriam Cooper describe ADHD as a neurodevelopmental condition: differences in how certain brain systems develop and work together, present early, lasting over time.
Those systems handle things like holding a plan in mind, waiting, stopping an action already underway, and keeping effort going when a task is boring. That is the real job description of "attention." It isn't about caring more.
This is why the same child can play one game for ninety minutes and lose track of a two-step instruction given thirty seconds ago. The interesting thing carries itself. The dull thing needs a system that is, in this brain, built differently.
What about sugar, screens and parenting?
These are the three answers people offer at family dinners, and they are the three that don't hold up.
The National Institute of Mental Health addresses this directly: research does not support the popular claims that ADHD is caused by eating too much sugar, by watching too much television, by parenting, or by social factors such as poverty.
That doesn't mean sugar and screens are irrelevant to your evening. A tablet at 8pm can absolutely make bedtime harder. A sugary snack before homework can make a wobbly hour wobblier. But making a hard evening harder is a different thing from causing a lifelong condition.
Thapar and Cooper also note non-genetic factors studied in connection with ADHD, including things like very low birth weight. These are associations found across large populations, not verdicts on any one family, and nothing on that list is "you let them watch too much YouTube."
So does parenting matter at all?
Yes. Enormously. Just not in the way guilt suggests.
Parenting doesn't decide whether a child has ADHD. It shapes how the days go: whether mornings end in shouting, whether your child grows up believing they are difficult, whether they learn tools that still work at twenty-five.
The 2019 clinical practice guideline from the American Academy of Pediatrics reflects this. For young children, training parents in behaviour management is recommended as a first-line approach. Not because parents caused the problem, but because parents are the people best placed to change the environment around it.
Think of it like eyesight. Nobody tells a parent they caused their child's short-sightedness. But getting glasses, putting them on before school, sitting nearer the front: that is a parent's work, and it changes everything about how the day feels.
What to say
When a relative says you're too soft. "ADHD is strongly genetic. The things that help him are a bit different from what helped us, and we're learning them."
When your child asks why their brain is like this. "You were born with a brain that's fast and full of ideas. It just needs help with the boring parts. That's not your fault and it's not something you have to fix alone."
When you catch yourself blaming you. Try saying it out loud, even in an empty kitchen: "I didn't cause this. I'm the person helping with it." Guilt eats the energy you need for the next morning.
When your child blames themselves. "Hard isn't the same as bad. Your brain finds some things harder than other kids do. We're going to make those things easier."
What to try this week
- Say the word out loud once, to your child. Not a speech. One sentence: "Your brain has ADHD, which is why starting things is tough. We're going to work with it." Children who have no explanation invent one, and the one they invent is usually harsher than the truth.
- Swap one judgement for one description. Instead of "he's so lazy in the morning," try "he can't start without a visible first step." A description points at something you can act on.
- Write down your own family history. A sibling who never finished a project. A parent who lost every set of keys. This isn't gossip; it's useful context, and your child's doctor will ask about it.
- Choose one external support instead of one more reminder. A checklist on the door, a timer on the table, a photo of the packed bag. Build the scaffolding outside the child's head, where the working memory load isn't.
Questions parents ask
Can ADHD be caused by trauma or a hard period at home? Stress and difficult events can affect attention, sleep and behaviour, and some of those signs can look like ADHD. That is one reason a proper evaluation looks at the whole picture over time rather than a single tough stretch. If something significant happened in your family, tell the clinician — it helps them get the assessment right.
Does ADHD skip generations? There's no clean on/off pattern. Heritability means a raised likelihood across a family, not a predictable rule. Two siblings with the same parents can land in very different places.
If it's genetic, can anything actually change? Yes. Heritable doesn't mean fixed. Skills grow, environments can be redesigned, and supports can be added. What changes is not the brain's wiring but how much friction the day creates for it.
What to carry out of this
Your child's ADHD is not a verdict on your parenting. It's a description of how their brain develops, and it came largely from the same gene pool that gave them their sense of humour.
What's left for you isn't guilt. It's the practical work: making the day visible, keeping one instruction on the table at a time, protecting your child's sense of themselves while the hard stuff gets easier.
If you have questions about your child's diagnosis, or about whether ADHD explains what you're seeing, talk to your child's doctor. Bring your notes and your family history. They are part of the evidence.
Understand the brain, not the blame.
CareTec turns your child's routine into steps they can see, one at a time — and shows you what's working.
Build your child's routine →Faraone, S. V., & Larsson, H. (2019). Genetics of attention-deficit/hyperactivity disorder. Molecular Psychiatry, 24(4).
Thapar, A., & Cooper, M. (2016). Attention deficit hyperactivity disorder. The Lancet, 387(10024).
Wolraich, M. L. et al. (2019). Clinical practice guideline for the diagnosis, evaluation, and treatment of attention-deficit/hyperactivity disorder in children and adolescents. Pediatrics, 144(4).
NIMH — Attention-Deficit/Hyperactivity Disorder
Published 2026-11-12 · Educational content, not medical advice.