Skip to Content

5 signs of autism in adults and the importance of getting a diagnosis

Autism is often underdiagnosed or misdiagnosed in adults with low support needs. Learn five signs of autism in adults and why a diagnosis is beneficial.

Tayla Holman
April 01, 2024
Some adults with autism may wear noise-canceling headphones or practice deep breathing to help reduce overwhelm from sensory input.

Autism spectrum disorder (ASD) — commonly shortened to autism — refers to a broad range of developmental conditions that affect social interactions, communication, learning and behavior. Because signs often appear within the first two years of life, autism is often considered a childhood developmental issue. However, autism is a lifelong condition, meaning it also affects adults.

Understanding autism in adults

According to the Centers for Disease Control and Prevention, 5.4 million American adults have ASD. However, recognizing the signs of autism in adults can be difficult. People with autism often learn to "mask," or hide, certain behaviors to avoid harassment or judgment. Some people learn to mask in childhood; others may do it unintentionally. Additionally, adults with autism who have low support needs — what was previously known as the "high-functioning" end of the autism spectrum — may not realize certain behaviors are associated with autism.

While doctors are getting better at spotting the signs of autism, challenges remain. Some autistic traits can mimic other conditions, such as ADHD and anxiety, making it harder to get an accurate diagnosis. Gender and racial differences also contribute to diagnosis challenges. Autism is still underdiagnosed in girls and women. And Black and Hispanic children are less likely to be diagnosed with ASD than white children. Although autism diagnoses have increased in recent years, more work needs to be done to reduce these disparities.

5 common signs of autism in adults

Many of the signs of autism in adults are similar to those in children, but they may be more subtle. If you think you or someone around you has autism, here are five common signs to look for.

Social challenges

One characteristic of autism is social difficulty, such as trouble understanding social cues or misspeaking unintentionally. Adults with autism may take things literally and have trouble understanding figurative language. Adults with autism who haven't been diagnosed may refer to themselves as "awkward" or feel different because they struggle to know how to respond in social interactions.

Repetitive or restrictive behavior

Often associated with obsessive-compulsive disorder, repetitive or restrictive behavior is a common sign of autism. Repetitive movements can include hand flapping, spinning or rocking. While these behaviors — called "stimming" — may appear distracting or disruptive, they serve a purpose. Adults with autism may also adhere to strict routines and dislike abrupt changes.

Sensory issues

Certain sensations can be uncomfortable for people with autism. Others may be highly soothing. Adults with autism can be sensory-seeking (enjoy sensory stimulation and look for more of it) or sensory-avoiding (avoid sensory stimulation because it feels overwhelming). Foods, smells, sounds and textures can all cause sensory-seeking or avoidant behavior. Some adults with autism cope with sensory challenges through stimming. This can help reduce sensory input, especially in crowds or loud environments, by allowing the person to focus on one specific thing. Other common strategies include wearing noise-canceling headphones or practicing deep breathing.

Narrow interests

Adults with autism often have a very narrow range of things they're interested in. They may hyperfixate on one or two subjects and often have a deep knowledge of those topics. This is frequently combined with increased memory recall. For example, an adult with autism may be able to recite facts about their favorite movie or animal, even if they gained that knowledge many years ago. However, having such narrow interests can make it more difficult for adults with autism to ‘fit in.’

Preference for solitude

Adults with autism may lack motivation to engage with others. This can go hand-in-hand with social difficulties, but it can also be a consequence of masking. The amount of effort that goes into trying to reduce certain behaviors can be exhausting. Adults with autism may prefer to be alone so they don't have to restrict themselves. Additionally, being alone means they can control their environment and reduce the risk of sensory overload that often comes from being out in the world.

How to start the conversation

If you believe someone you know has autism, you might be wondering how to start the conversation. First, it's important to be empathetic. Ask them what they know about autism and if they're familiar with the signs and behaviors. If they say yes, ask if they or someone they know has been diagnosed with ASD.

This is a sensitive subject; you may not want to go any further if they seem uncomfortable at this point. If they seem open and positive, continue the conversation by talking about people you know who are on the spectrum (if this is true). You can then mention some of the behaviors you noticed and ask if they've considered seeking an autism diagnosis.

How you approach the conversation will depend on your relationship. If you're close with the person, approach the subject from a place of love and understanding. You don't want to sound accusatory or like you think something is wrong with them. Avoid offering unsolicited advice to someone you don't know well.

Benefits of an ASD diagnosis

If you or someone you know has reached adulthood without an ASD diagnosis, you may be wondering if it's worth pursuing a diagnosis now. While this is a personal decision, getting a diagnosis can have benefits. For example, it can open the door for support services and accommodations, whether at school, in the workplace or in a healthcare setting. A formal diagnosis can also serve as validation if you've always felt "different" or out of place. It can provide a better understanding of yourself and your behaviors, enabling you to find ways to manage them.

Autism is a spectrum, and no two people experience it the same way. As doctors get better at recognizing the signs and autism awareness increases, more adults will likely receive a diagnosis — and that's a step in the right direction.

April 01, 2024