Autism often undiagnosed in adults, experts warn
Advocacy grows, but many adults receive their first diagnosis later in life as researchers note masking and gender differences complicate detection
Autism spectrum disorder in adults is often overlooked, even as advocacy and education expand. In the United States, about 1 in 36 children are identified with autism, according to the Department of Health and Human Services. But many people learn they are on the spectrum only later in life, or remain undiagnosed altogether. Autism Speaks, a leading advocacy group, says roughly 1 in 45 adults in the United States is diagnosed with autism spectrum disorder. National Institutes of Health data indicate that about 5.4 million American adults are living with autism. The numbers reflect a broad range of experiences, from mild to severe, and they underscore the need for better recognition of autism across ages. Experts say that gaps in screening, varying symptom presentation, and social stigma have contributed to delayed diagnosis for adults who could benefit from support and services.
Autism is defined by challenges with social communication and the presence of restricted or repetitive behaviors. In adults, the symptoms can appear differently than in children and may change with age. Common hallmarks highlighted by Autism Speaks include feeling awkward in social situations, difficulty understanding others' feelings or thoughts, preferring to be alone, trouble making friends, and a tendency to follow social rules inconsistently. Verbal and non-verbal cues can include struggling with eye contact, responding in a blunt way, or taking things literally. Repetitive or restrictive behaviors may show up as a strong preference for routines, noticing small details that others miss, or having intense and specific interests. Adults on the spectrum may not display every characteristic, and the way symptoms manifest can shift over time.
Masking and gender differences: For many autistic adults, masking — the act of hiding symptoms to fit in — is a common strategy. Some individuals imitate the speech or body language of others, force eye contact, or use subtle stimming to seem more typical. Masks can help people navigate school, work, and relationships, but prolonged masking can take a heavy toll on mental health, leading to fatigue, anxiety, and a sense of isolation. Research and advocacy groups note that girls and women are more likely to mask than boys and men, which may contribute to later or missed diagnoses in females. Cultural expectations about women’s social behavior can further obscure signs of autism and delay evaluation.
Road to diagnosis and supports: The autism spectrum is broad, and symptoms vary widely among individuals. Major life changes — moving to college, starting a new job, or changes in family status such as marriage or parenting — can alter how symptoms present and when they become more noticeable. For adults who suspect they may be on the spectrum, experts advise pursuing a formal evaluation. Start by talking with a primary care physician or checking with an insurer for a list of qualified professionals who diagnose autism in adults. Some insurance plans may impose age-related restrictions on coverage for autism evaluations, so initiating the process earlier can help. A clinician will typically take a detailed history, observe communication and social interaction patterns, and may refer to developmental specialists or psychologists. Recognizing the diversity of the spectrum is essential to ensure people access appropriate supports, from therapy and social skills training to employment accommodations.
Experts emphasize that understanding autism as a spectrum, rather than a fixed set of traits, can improve outcomes. For adults who suspect they are on the spectrum, engaging trusted family members or partners in screening and planning can help with access to care. While the diagnostic process can be lengthy, many people report benefits from evaluation, including validation, tailored therapies, and clearer pathways to services that support daily living and mental health. Health systems are increasingly recognizing adults with autism, but barriers remain, including stigma and gaps in adult-focused services. As awareness grows, clinicians urge cautious, evidence-based approaches to diagnosis and treatment that respect each person’s unique profile and goals.
