Adult Onset ADHD Totally Different Than Childhood ADHD

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Ever since I blogged about 5 Holistic Ways To Treat ADHD a few weeks ago, I’ve gotten dozens of emails from readers wondering if the same approach would help them with their adult ADHD too.

So this is the perfect time to update you on the latest medical research about adult onset ADHD and give you a few additional recommendations.


Although adulthood ADHD can absolutely simply be a continuation for childhood ADHD, researchers are now finding out that there is a separate, totally different, adult onset ADHD syndrome.


This is important to understand, because currently to have a diagnosis of ADHD as an adult, you must have been exhibiting symptoms since at least 12 years old.

That diagnostic criteria is harmful and limiting and may discourage health care practitioners from addressing and treating adults with ADHD (or not even considering the diagnosis at all!) based on the false belief that ADHD must present in childhood.








Two studies — both published in JAMA Psychiatry (July 2016) — looked at adult onset ADHD.

Both suggest that late onset, adulthood ADHD is actually the most common form of adult ADHD… more common than ADHD that started in childhood and continued through to adulthood.


The first study:

  • Looking at over 5,200 patients born in 1993, researchers followed individuals diagnosed with ADHD during an almost 20 year follow up period.
  • Researchers identified 393 individuals diagnosed with ADHD during childhood (age 11). Following these children with childhood-onset ADHD, only 60 individuals continued to have ADHD symptoms into adulthood.
  • Bottom line: only 17% of patients with childhood ADHD continued to have ADHD as an adult.
  • Researchers identified 492 individuals who had ADHD as an adult, and looking back found that only 12% of these individuals met the diagnostic criteria for having had the childhood form of ADHD.


So the overlap here is very slim — childhood ADHD generally did not persist into adulthood and adult ADHD generally did not start in childhood.

This is big news for the medical field, because we generally had assumed that childhood ADHD and adulthood ADHD were the same thing, and the only difference was time of diagnosis.

We assumed that adults with ADHD had a diagnosis that was missed during childhood, and this study suggests that that might not be the case.

We also assumed that children who had childhood ADHD were likely to have the disorder persist for a lifetime, and this study suggests that that might not be the case at all.

In fact, this study suggests that if you have ADHD as a child, you are unlikely to have it as an adult (outgrowing ADHD) and so treatment for ADHD should not be assumed to be lifelong.

And if you have ADHD as an adult, it’s not that you necessarily were undiagnosed earlier on… in fact, in the majority of cases, the ADHD was not present during childhood.

If there is a difference between the two syndromes, then perhaps this suggests there is a difference in the progression and resolution of the disorder, and also perhaps a difference in the treatment approach as well.


The second study:

  • Researchers looked at over 1,000 patients born in 1972 – 73, and followed them for an almost 40 year period.
  • This study showed that almost 90% of adult ADHD cases did not have clinical symptoms or diagnosis of ADHD in childhood, nor did they have neuropsychological deficits in childhood or adulthood, nor did they show polygenic risk for childhood ADHD.
  • They found that the childhood ADHD group and the adult ADHD group were almost completely non-overlapping… suggesting again that adult onset ADHD is completely different from childhood ADHD and may have a completely different mechanism of action.


Childhood ADHD is considered a neurodevelpmental disorder… but is it possible that adult-onset ADHD is not a neurodevelopmental disorder at all?

If that is the case, then approach that helps childhood ADHD may not at all help adult ADHD.

Previous studies focusing on holistic support for childhood ADHD may not take into account all that can be done to support adult-onset ADHD. Although a focus on higher quality sleep, omega 3 fatty acid supplementation, and eating sulforaphane rich foods (broccoli!) are brain supportive and are all shown to support childhood ADHD, what else can be done for adult onset ADHD?


A new study aimed to find out.

Published just this year in Medicine & Science in Sports & Exercise, researchers looked at whether or not exercise can help mitigate ADHD symptoms.

The Study:

  • It has been long proven that exercise boosts cognitive function.
  • It was not known if that cognitive boost has any therapeutic effect in adults with ADHD.
  • So researchers took 32 men with adult diagnosis of ADHD, and tracked their ADHD symptoms both before and after a 20 minute bout of rigorous exercise on a stationary bike.
  • After the exercise, participants continued on to complete 40 minutes of cognitive testing.

What they found was that for adults with ADHD, one single 20 minute bout of exercise (in this study, cycling):

  • significantly elevated the participants motivation in completing tasks afterwards,
  • significantly elevated their endurance and vigor while undergoing 40 minutes of subsequent cognitive testing,
  • significantly increased energy levels,
  • and significantly reduced feelings of confusion, depression and fatigue, when compared to a non-exercise control group.
  • Notably, exercising did not make a significant difference in leg hyperactivity, meaning that the increase in energy level and boosted motivation to complete cognitive tasks after exercising did not increase agitation or fidgeting.
  • So, the participants enjoyed boosted energy and drive with no increase in hyperactivity behaviors. Woot!

So that’s a win for exercising — making it a very important, non-pharmacological treatment for adult ADHD.

Finding ways to incorporate short bouts of physical activity into the typical work day (**especially** when facing a cognitive challenge where you need increased concentration like prior to a meeting or stressful phone call or tension filled commute) will help you stay focused, keep your energy high and lift the depression and fatigue that can typically accompany an ADHD person when they are trying to do prolonged tasks that feel *boxed in* and constricting.


These feelings of constriction and agitation contribute to the fact that adult ADHD patients have twice the rate of depression, anxiety and substance abuse.

In fact, adults diagnosed with ADHD have a mortality rate that is DOUBLED.

And in particular, death from accidents.

So if exercising is a way to boost focus and mood while keeping physical symptoms stable… this is a very important intervention for folks with ADHD to know about.

I believe firmly (and blogged about this a few weeks ago) that the same approach of allowing lots of physical activity in children with ADHD can really help them in a school setting (or better yet, homeschool them so there are unlimited opportunities to take breaks, get exercise, and can refocus before tackling cognitive tests or schoolwork.)




In addition to exercise, I’ve found several supplements that seem to help boost cognitive function and make a noticeable difference in adults with ADHD:

  • The first, just like in childhood ADHD, are Omega 3 Fatty Acid supplements (my favorite being Krill Oil.)
  • The second, in young adults (teens and 20 year olds) taking a Sulforaphane Glucosinolate supplement has been proven to decrease hyperactivity and repetitive movements.
  • Taking a neuro-stabilizing trace mineral supplement (like Concentrace Mineral Drops) with trace amounts of magnesium, potassium, lithium, boron, and other crucial minerals that your brain needs to function effectively can be extremely helpful.
  • Lastly, consider naturally boosting your brain’s level of dopamine by supplementing with the precursor L-Tyrosine, which converts into dopamine and provides a calming, stabilizing influence to help increase focus and boost memory.



Teacher with student

The main thing I wanted to get across in today’s article is that childhood ADHD typically does not extend into adulthood and adulthood ADHD typically did not present in childhood.

Although there is some overlap, please don’t set the expectations on a child with ADHD that they are locked into having the same challenges as an adult that they might have currently as a child.

While great sleep, Omega 3 supplements, and eating your broccoli are great lifelong habits to get into, it’s important that you present to your child the idea, at least the possibility, that they will likely outgrow some of the symptoms of ADHD as an adult.

And if you are an adult with ADHD, it’s important to be proactive now about scheduling in physical activity and finding ways to access physical activity into your work day.





Even if you have to do some jumping jacks before entering a meeting room, go out for a quick run at lunch time, or bike to and from work… having an outlet that you can turn to if you feel fatigue or irritability creeping into your day can make a significant difference to your quality of life.

xoxoxox, Laura