Are you one of many adults living with undiagnosed ADHD? These are the 10 hidden signs the experts want you to know

Words: Amy Mica Marsden. Images: Shutterstock.

When was the first time you heard of ADHD? Was it on TV, with zany and hyperactive characters who struggled to sit still? Or in school, with teachers using it as an admonishment for a disruptive student?

Wherever you first came into contact with ADHD, there’s a good chance it came with negative stereotypes.

It’s many of these stereotypes – and outdated medical information – that left many adults struggling with undiagnosed ADHD for years.

In 2023, an estimated 15.5 million US adults received an ADHD diagnosis, half of whom were adults. However, a recent national survey commissioned by The Ohio State University Wexner Medical Center and The Ohio State University College of Medicine found that up to 25% of adults in the US suspect they may be living with undiagnosed ADHD – and there’s a chance the real number could be even higher.

Why symptoms get missed

‘Until the 1990s, it was generally accepted that people grew out of ADHD, so it was considered a childhood diagnosis,’ says Dr Jennifer Cork, LCSW and certified autism specialist. ‘This means that Gen X is the first generation of adults whose ADHD was recognized as a lifelong diagnosis.’

It wasn’t until 2013 that the 5th version of the Diagnostic and Statistical Manual of Mental Disorders (a.k.a. the DSM-5) added clarification on how ADHD might present in older adolescents and adults. 

‘Additionally, there has been much more research on ADHD in women and girls in the last 5 to 10 years. All of this has led to a greater awareness of what ADHD is, and what it can look like other than just people who can’t pay attention and sit still,’ says Dr Cork. ‘Many adults are getting diagnosed after their kids receive diagnoses and they realize that many of the things that their child is struggling with are things they also struggled with.’

Women hitting perimenopause also typically find their symptoms become much more noticeable, as ‘changes in estrogen can impact dopamine levels, which are already lower in the ADHD brain,’ Dr Cork explains. ‘This means that women who may have had coping skills that masked their ADHD will start to struggle to access these skills, leading to a late diagnosis.’

To help you better understand the subtle symptoms of ADHD, we took a look at some common ‘hidden’ symptoms of the disorder and what they might mean below.

10 hidden ADHD signs you might have missed

1. Emotional dysregulation

If you often find your mood bouncing between extremes, you could be experiencing emotional dysregulation, a common experience for those with ADHD. It’s characterized by difficulty managing intense emotions, feeling easily frustrated, or emotions that feel too strong for the situation or in comparison with others.

2. Struggling to prioritize to-do lists

ADHD affects the brain’s executive functioning abilities – in other words, the mental functions that help you plan, adapt, think creatively, store short-term information, and more. When your executive functioning is inhibited, your brain struggles to decide which tasks are more important than others, which can easily lead to overwhelm. This can apply to everything from big work projects to even the ‘simplest’ of morning routines.

3. Addiction

ADHD brains struggle to regulate dopamine levels and often don’t produce enough of this essential chemical. Instead, people with ADHD might seek out dopamine from external places, which, when combined with differences in impulse control, may lead to a spiral of addiction. Addictions can be anything from alcohol and substances to sex, gambling, shopping, and more.

4. Frequent accidents and injuries

Always finding bruises that you don’t remember getting? Constantly bumping into table corners or falling over? Clumsiness can be a sign of ADHD, as the disorder can affect your motor control and proprioception (the body’s ability to know where it is in space). Inattentiveness associated with ADHD also means you may not notice certain obstacles in the way until it’s too late.

5. Staying up late

Similar to addiction, dopamine-seeking behavior can mean you often stay up late scrolling on your phone or struggle to stop the fun activity you were doing – even at the cost of your sleep. Many people with ADHD also have what’s known as Delayed Sleep Phase Syndrome, where the body’s circadian rhythms naturally operate around 2-3 hours later than those without the disorder, meaning you don’t get tired at the same time as neurotypical people. According to ADDitude magazine, up to 80% of people with ADHD are night owls. 

6. Insomnia and other sleep issues

Aside from staying up late and delayed circadian rhythms, people with ADHD also notably struggle to fall asleep and may even wake up after just a couple of hours. This can be down to racing thoughts keeping you awake and a delayed release of the sleep hormone melatonin. When it comes to 2–3 a.m., the body’s natural cortisol spike to prepare for waking can affect those with ADHD more, leading to a wide-awake feeling even though you only slept a short time. 

7. Binge eating

For people with ADHD, food can trigger dopamine release cycles that are particularly hard to break out of. You may spend a lot of time thinking about food and planning what you’ll eat, because your brain’s dopamine-seeking behavior has been trained to see food as a dopamine hit. However, binge eating can often lead to shame cycles once that dopamine hit has passed, and many struggling with binge eating disorders hide it from their loved ones.

8. Struggling with task initiation and completion

For those with ADHD, novelty is a big motivator. This means that starting a new project, hobby, or routine can feel exciting and fun at first, but your enthusiasm quickly peters out once the novelty wears off. You may start a journaling habit and stop by day 5, go all in on a new hobby only to leave it basically unused, or struggle to finish books or TV shows you started. When it comes to tasks that require a lot of energy or brainpower, you may find yourself procrastinating until the last possible second due to executive functioning issues. Ever noticed your house is suddenly at its tidiest at the time your taxes are due…?

9. Interrupting people and other social issues

If you often find yourself jumping into conversations before it’s your ‘turn’ to speak, this could also be a symptom. ADHD affects impulse control and activity levels, meaning you struggle to hold back the impulse to speak once your racing mind has formed a thought. This is not a sign of rudeness or a lack of care, but just how your brain works. When it comes to socializing, you may also often zone out or struggle to pay attention to a story, go off topic, or struggle to stop yourself from talking too much. 

10. Time blindness

Think you can get out of bed and be ready in the 15 minutes it’ll take your bus to arrive? Or do you always end up late to everything, despite leaving what you feel is sufficient time to get there? You may have time blindness, another possible symptom of ADHD. People with ADHD may chronically underestimate how long a task will take to complete, or get lost in hyperfocus and accidentally lose hours of your life to scrolling or another seemingly ‘short’ task.

ADHD misconceptions

‘In my opinion, ADHD is a very misunderstood disability, which leads to a lack of adequate understanding and support,’ says Dr Cork. ‘Unfortunately, because of the lack of understanding, when ADHD-ers are struggling with things like showing up to work on time, finishing projects, struggling to prioritize, etc., they are met with judgment, rather than accommodations that will set them up for success.’

It’s important to remember that if you struggle with any of the above, you’re not lazy, inconsiderate or incapable – your brain just functions differently. 

Dr Cork adds that by judging those with ADHD and denying them accommodations, ‘systems are losing out on the strengths this group of individuals has to offer, such as being out-of-the-box thinkers, entrepreneurs, and bringing dynamic energy to spaces, workplaces, and social gatherings.’

Additional Resources

If you’re struggling with any of the above, help is out there.

More information on ADHD: visit add.org or the American Psychiatric Association

Addiction: Contact the SAMHSA National Helpline in the US on 1-800-662-4357 for free, confidential, 24/7 treatment referrals and information.

Eating disorders: Call the free National Alliance for Eating Disorders helpline in the US on +1 (866) 662-1235