What causes ADHD?

Your guide on the factors that can increase the risk of developing ADHD, from genetics, to environment, and trauma.

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Alexandra Cristina Cowell
Medically reviewed by Alexandra Cristina Cowell Clinical Support

Reading time: 1 min

Uploaded on: January 28, 2026

We won’t beat around the bush – we don’t exactly know. It’s a complex condition, and we’re still learning more about it and the factors that might be responsible. At the moment, it’s thought to be caused by a combination of genetics, environmental factors, and developmental issues with the nervous system.

  • ADHD is a genetic condition. It’s more likely to develop in biological relatives of those with ADHD.
  • Factors during pregnancy like maternal obesity or diabetes can increase the risk of ADHD outcomes.
  • Low birth weight and premature births are also associated with increased risk of ADHD-related symptoms.
  • Diet doesn’t cause ADHD, but it can affect behaviour and development.
  • Traumatic brain injuries are often followed by mental illness, and can cause ADHD to develop.

Read next:

Genetic causes of ADHD

Environmental causes of ADHD

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Reading time: 1 min

Uploaded on: January 28, 2026

Dr Daniel
Medically reviewed by Alexandra Cristina Cowell Clinical Support Registered with GMC (00001) January 28, 2026 Meet Alexandra Cristina Cowell
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Written by Focused Content Team
Last updated on May 21, 2026
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