The causes of autism

Possible causes

Evidence suggests that autism may be genetic. Scientists have been attempting to identify which genes might be implicated in autism for some years. Autism is likely to have multiple genes responsible rather than a single gene. However, it is not caused by emotional deprivation or the way a person has been brought up.

There is no link between autism and vaccines. Much research has been devoted to this issue over the years and the results have comprehensively shown there is no link. Find out more on the NHS website.

Myths about the causes of autism

Bad science and misinformation have created myths about the causes of autism. Autism is not caused by vaccines or paracetamol.

Myth: Vaccines

A lot of research has looked into whether vaccines cause autism. The answer is very clear: vaccines don’t cause autism.

In the 1990s, some bad science caused a ‘health scare’ about the measles, mumps and rubella (MMR) vaccine. This is where the worries about autism and vaccines came from. This fake research has been shown to be completely wrong.

The doctor who published it had made up data and was dishonest about his findings. Because of this, he was ‘struck off’ (banned from working in medicine forever) by the General Medical Council.

Even though the research was fake, fewer people got the vaccine. This led to outbreaks of deadly disease.

Since then, a huge amount of new research has been done to make sure the MMR vaccine is safe. It showed there is no link between the MMR vaccine and autism.

The MMR vaccine is safe. And the new MMRV vaccine (which also includes ‘varicella’ – chicken pox) is also safe.

All vaccines must go through many tests to make sure they are safe. No vaccines cause autism.

Watch a short video and read more information about vaccine safety on the NHS website.

Myth: Paracetamol

There is no evidence that taking paracetamol (known as Tylenol and acetaminophen in the US) during pregnancy causes autism.

NHS advice is that paracetamol is the first choice of painkiller if you are pregnant or breastfeeding and it does not harm your baby.

In September 2025, the Medicines and healthcare products regulatory agency (MHRA) made a statement confirming that "taking paracetamol during pregnancy remains safe and there is no evidence it causes autism in children".

Dr Alison Cave, Chief Safety Officer at the MHRA, said: "Pregnant women should continue to follow existing NHS guidance and speak to their healthcare professional if they have questions about any medication during pregnancy."

Paracetamol is commonly used to manage pain and fever. Dr Cave highlights that "Untreated pain and fever can pose risks to the unborn baby, so it is important to manage these symptoms with the recommended treatment."

Is there a 'cure' for autism?

There is no known 'cure' for autism. We also believe that autism does not need a 'cure' and should be seen as a difference, not a disadvantage. We also warn people about fake cures and potentially harmful interventions here.

This does not mean that autistic people do not face challenges, but with the right support in place, they are more than capable of living fulfilling and happy lives.

Because autism is a 'spectrum' condition it affects different people in different ways. It is therefore very difficult to generalise about how an autistic person will develop over time. Each person is different, and an intervention or coping strategy which works well with one person may not be appropriate or effective with another.

The characteristics of autism can present themselves in a wide variety of combinations. Two people with the same diagnosis can have a very different profile of needs and skills.

Valuing neurodiversity

There is a growing movement among autistic adults who don't think in terms of 'curing' a disorder but instead of celebrating diversity. This is not to suggest that autistic people or those with other diagnoses do not find life challenging, but that they see it as a different way of communicating, thinking, and interacting.

What autistic people have to say

Through our Stories from the Spectrum series, we’ve spoken to several autistic people, who have shared their thoughts on this topic, what being autistic is like for them, and some of the positive aspects of being autistic.

"I just seem to see and think about people and the world in a different way. It's part of who I am."

John Clark

John Clark, autistic filmmaker, told us: "I just seem to see and think about people and the world in a different way. For instance, I am both confused and fascinated by idioms. It’s part of who I am. I used to be very self-conscious about people liking and accepting me, but now, I just think, “take me or leave me”. We’re all different. Some people seem to find ‘live and let live’ a difficult mantra to grasp though."

Patrick Samuel, autistic artist and musician, said: "My autism makes it easy for me to do things a lot of non-autistic people may struggle with. I work intensely when I’m painting, writing, composing or doing anything creative. I think being autistic also contributes to my aptitude in problem solving and pattern recognition, which can help me research a highly specialised subject and give talks on it."

Harri Wilson, a Stories from the Spectrum contributor and autistic junior doctor, said: "I always notice lots of details other people miss and this can be really important in making the right diagnosis at work, or picking up that a patient is deteriorating. I also have an excellent memory, which really helps in my job. I can’t really recognise or remember faces though – this can make things tricky when many of my colleagues wear the same uniforms!"