Do environmental factors cause ADHD?

When it comes to Attention Deficit Hyperactivity Disorder (ADHD), you may wonder if nature or upbringing plays the biggest role in its occurrence.

For example, let’s say more than one of your children has been diagnosed with ADHD. Maybe you are wondering if you are doing something to provoke it. (You probably aren’t, by the way).

Or, if you or your partner has ADHD and your child is diagnosed with it, you might be wondering if the diagnosis was inevitable. (In short: Inevitable, no. Likely, yes).

The truth is, says Jessica Myszak, a licensed psychologist with The Help and Healing Center, “The cause of ADHD in an individual, like many other health problems, cannot be clearly identified. “

Here’s what we know: ADHD is a neurodevelopmental disorder, which means that a brain with ADHD forms differently than most others.

In other words, “you don’t develop ADHD,” explains Amy Marschall, licensed clinical psychologist. “Neurological differences seem to be something you were born with. “

It is these neurological differences that predispose you to ADHD and its symptoms.

Environmental factors do not directly cause ADHD. At least, not alone.

Nature, aka genetics, plays a big role. But your environment can also contain factors that lead to ADHD.

In fact, Myszak says, “there is clear evidence that certain environmental risk factors are strongly linked to subsequent ADHD diagnoses.”

These environmental factors can include:

  • in utero, or in the womb, exposure to substances or chemicals
  • early birth or low birth weight
  • environmental toxins
  • diseases like bacterial diseases and encephalitis

In utero exposure

2012 research has shown that pregnant women who drink alcohol or smoke tobacco are more likely to have a child with ADHD.

A 2018 study found that children were at greater risk for ADHD if their mothers were heavy smokers, while another study found that mothers who drank 4 or more alcoholic drinks at one time were likely to have a child with ADHD.

Maternal nutrition can also play a role, as can infection during pregnancy.

“Special medications, such as antidepressants, antihypertensives and caffeine,” Myszak explains, may also be considered.

The American Psychiatric Association adds that babies born early or with low birth weight also have a greater chance of developing ADHD.

Exposure to environmental toxins

These can be toxins that you were exposed to in utero or during your childhood. They may include:

  • lead
  • Mercury
  • pesticides
  • specific chemical compounds

For example, the Centers for Disease Control and Prevention (CDC) says that lead appears to be associated with inattention, hyperactivity and impulsivity. These are all symptoms of ADHD.

The organophosphate pesticide, which is commonly sprayed on lawns and agricultural products, has been shown in a 2016 study affect the neurological development of children. This is why some researchers believe that it could play a role in the onset of ADHD.


A 2017 study discovered that bacterial meningitis can also be a risk factor for ADHD. Bacterial meningitis is a serious bacterial disease that is spread from person to person and through food.

Meanwhile, a Taiwanese study 2015 found that encephalitis, which is inflammation of the brain due to infection or an autoimmune response, could also be a risk factor for ADHD.

The truth? Researchers are not entirely sure what the root cause of ADHD is. It’s probably because one thing doesn’t cause ADHD on its own.

“Since every person is an individual, we can never say for sure ‘X causes Y,’ says Marschall.

One cause is fairly well supported by studies of twins and families: Genetics appear to play a significant role in the onset of ADHD.

“Children of siblings with ADHD are 9 times more likely than other children to also have ADHD, with heritability estimates ranging from 74% to 88%,” Myszak said, citing a 2005 study.

Yet just because genetics predispose someone to ADHD doesn’t mean they’ll get it.

A 2015 study found that there are many risk factors for ADHD. In most cases, one risk factor was not enough to cause ADHD.

“Instead, ADHD typically results from several genetic and environmental risk factors that cumulatively increase a person’s likelihood of suffering from ADHD,” Myszak explains.

“It can be very complicated to distinguish environmental factors from genetic factors because family members not only share genetics but also certain lifestyle factors that can also contribute to ADHD risk. ”

In other words, all factors are important, since it is the cumulative effect of these factors that causes ADHD.

Yes, the evidence suggests that other factors play a role as well.

“Over the past two years, there has been more research into brain differences in people with ADHD, and there have been consistently identified variants in the ADHD brain,” Myszak explains, referring to a 2019 study. “It’s not yet enough to change the way we diagnose ADHD, but it’s exciting and promising. “

It also appears that some ADHD diagnoses arise as a result of brain damage, as seen in a Research report 2014. This includes damage caused by:

  • early life injuries
  • head trauma
  • atypical brain development

There are a lot of rumors and myths surrounding ADHD. Many of them harm parents or make them feel guilty for doing something wrong with the way they are raising their children.

But these myths seem to be just that: myths.

For example, the CDC states that there is no scientific research supporting the idea that ADHD is caused by:

  • eat too much sugar
  • watch too much tv
  • poverty
  • family discord

ADHD is a neurodevelopmental disorder and current research suggests that genetics play a major role. Because genetics can predispose someone to ADHD, it cannot be avoided.

According to Myszak, there are some steps parents expect parents can take to make sure their babies are healthy overall:

  • receive prenatal care
  • avoiding exposure to drugs, alcohol, and tobacco during pregnancy
  • limit exposure to environmental toxins like pesticides and lead

However, you can also take steps to help manage ADHD symptoms, such as:

  • set up a structure and consistent expectations with your child
  • do daily physical activities
  • a lot of sleep
  • avoiding stimulating activities, especially before you need to concentrate or sleep

Stimulating activities can include electronics, computers, video games, and television.

“The data on diet is mixed at this point, so I would advise parents to talk to their pediatrician about what is best for their child,” says Marschall.

Yet the CDC recommends establishing healthy eating habits as part of a routine and a way to stay healthy.

ADHD is a little different for everyone, and symptoms can vary between childhood and adulthood.

That said, according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), general symptoms of ADHD include:

  • be forgetful
  • be easily distracted
  • be prone to reckless behavior
  • lose or misplace things
  • be prone to impulsive behavior
  • lack of motivation for specific activities
  • difficulty in organizing things
  • difficulty completing tasks

Since ADHD is primarily diagnosed based on behavior, no medical test exists to detect it. Instead, you or your loved one will have a few sessions with a mental health professional, such as a psychologist or psychiatrist. They can assess behavior, talk to teachers and family members, and come to a diagnosis.

Treatment for ADHD varies depending on your symptoms. But one Research report 2005 has found that it typically includes a combination of:

  • medication
  • psychotherapy
  • behavior management
  • organizational and social skills training


People with ADHD may be prescribed medications, which have been tested in a Research report 2018. These include stimulants to manage impulsive behavior and non-stimulants to help with memory and attention.


Talk therapy can help people with ADHD develop the tools they need to better deal with social situations, relationships, and stress.

Behavior management

Behavior therapy works with a person with ADHD to reinforce positive behaviors and reduce negative behaviors. It can help them do better at school, at work and in their social life.

Organizational and social skills training

People with ADHD may also benefit from training in organizational skills or social skills. Organizational and social skills therapies can include:

There are a number of ADHD organizations that can be helpful in connecting people with ADHD, or parents of children with ADHD, to the resources they need. These include therapy, support groups and workshops for people with ADHD.

You can contact :

If your child with ADHD is having difficulty in school, you may also find it helpful to contact school services or parent groups.

ADHD does not seem to have a single cause.

Instead, ADHD has a number of causes, making it difficult to know exactly why a person is being diagnosed.

Yet genetics and environmental factors play an important role.

The good news is that if you or your child has ADHD there are many options once you are diagnosed with how to manage the condition and thrive with it.

Simone M. Scully is a new mom and journalist writing about health, science and parenting. Find it on his website Or on Facebook and Twitter.