Eczema is one of the most common skin conditions in the world, affecting roughly 204 million people globally. That translates to about 2.6% of the entire population, though the rate is significantly higher in children and varies widely by country, age, and how you define the condition. If you or someone in your family has it, you’re far from alone.
Global and U.S. Prevalence
Worldwide, about 129 million people have atopic dermatitis, the most common form of eczema. Children are affected at roughly twice the rate of adults: 4% of children compared to 2% of adults. In the United States, the numbers run considerably higher. CDC data from 2024 shows that 12.7% of American children ages 0 to 17 have diagnosed eczema, with similar rates in boys (12.2%) and girls (13.3%). That rate holds steady across age groups and doesn’t differ meaningfully between kids in cities and those in rural areas.
Those figures likely undercount the true burden. A U.S. population survey found that 10.7% of people had symptoms meeting the criteria for eczema, but only about a third of them (37.1%) had ever received a formal diagnosis. Extrapolated nationally, that meant roughly 31.6 million Americans had eczema symptoms, with the majority managing the condition on their own or never seeking medical care at all.
How Rates Have Changed Over Time
Eczema is not just common; it’s becoming more common. Global dermatitis cases rose from about 174 million in 1990 to 241 million in 2021, a 38.8% increase. Atopic dermatitis specifically climbed by 20% over the same period, reaching 129 million cases. Some of that increase reflects population growth and better diagnosis, but the trend is consistent enough across countries that researchers consider it a genuine rise in disease burden rather than a statistical artifact.
When Eczema Typically Starts
Eczema overwhelmingly begins in early childhood. About 45% of cases start within the first six months of life, 60% appear during the first year, and 85% develop before age five. For most children, the condition improves with time. Fewer than half achieve complete resolution by age seven, and about 60% see their eczema clear by adulthood. That still leaves a substantial number of people carrying eczema into their adult years, sometimes after a gap of symptom-free time in adolescence.
Not all eczema starts young. The population survey data found that for broader eczematous conditions (beyond just atopic dermatitis), peak onset actually occurred between ages 18 and 29. Adult-onset eczema is a recognized pattern, particularly contact dermatitis triggered by workplace exposures or new allergens.
Different Types and How Common Each Is
When people say “eczema,” they usually mean atopic dermatitis, but several related conditions fall under the umbrella:
- Atopic dermatitis is the most common chronic form, affecting 2 to 3% of adults and up to 25% of children at some point during childhood.
- Contact dermatitis happens when the skin reacts to a specific irritant or allergen. Between 15% and 20% of people experience it at some point in their lives, making it extremely common, though episodes are often short-lived.
- Seborrheic dermatitis causes flaky, red patches on oily areas like the scalp and face. It’s the condition behind most dandruff.
These conditions overlap. Someone with atopic dermatitis is more likely to also develop contact dermatitis, and both can coexist with asthma and hay fever as part of a broader allergic pattern.
Most Cases Are Mild
The severity picture is reassuring for most people. Community-based studies show that about 84% of atopic dermatitis cases are mild, 14% are moderate, and only 2% are severe. That distribution helps explain why so many cases go undiagnosed: people with mild eczema often treat dry, itchy patches with over-the-counter moisturizers and never see a doctor about it. Among those with moderate to severe symptoms, roughly a third report sleep disturbances, and about a quarter deal with symptoms that never fully go away between flares.
Who Gets It More Often
Eczema does not affect all populations equally. Prevalence is notably higher in Africa and Oceania and lower in the Indian subcontinent and Northern and Eastern Europe. Within African populations, rates range widely from about 4.7% to 23%, reflecting differences in climate, urbanization, and genetics. In the U.S., eczema rates tend to be higher in lower-income groups, a pattern that likely reflects differences in housing conditions, environmental exposures, and access to treatment rather than biology alone.
Where you live matters too. A systematic review of 26 studies found that 19 showed a higher risk of eczema in urban areas compared to rural ones, with 11 of those reaching statistical significance. The reasons aren’t entirely clear, but leading theories point to greater air pollution exposure, less contact with diverse microbes during early childhood, and differences in indoor environments like central heating and carpeting. Only one study found a significantly lower risk in urban settings.
Why So Many Cases Go Undiagnosed
The gap between how many people have eczema symptoms and how many receive a diagnosis is striking. With nearly two-thirds of symptomatic people in the U.S. never getting a physician diagnosis, eczema is substantially undertreated as a population-level condition. Many people assume their dry, itchy skin is normal or seasonal, especially if symptoms are mild. Others manage with drugstore creams and never consider that what they’re dealing with has a name and more targeted treatments available.
This matters because even mild eczema that goes on for years can damage the skin barrier over time, increasing sensitivity to irritants and allergens. People with undiagnosed eczema are also more likely to have comorbid conditions like asthma and allergic rhinitis that could benefit from a coordinated treatment approach.