Nearly All Adults May Carry Demodex Mites—But Most Never Notice Them (2026)
Demodex mites are microscopic, eight-legged arthropods that commonly live in human hair follicles and sebaceous glands. They are often called “face mites” because they are especially associated with facial skin, eyelashes and eyebrows. The surprising part is how difficult it is to answer a seemingly simple question: How many adults actually have Demodex mites? Some studies have reported extremely high prevalence, including one molecular study in which Demodex DNA was detected in 100% of adults over 18 in a small sample . But a much larger 2025 systematic review and meta-analysis estimated a global pooled prevalence of approximately 35% across the available studies. The key lesson: “100% of adults have Demodex” is too absolute as a general population statement. The available evidence suggests that Demodex is extremely common in adults, but the measured prevalence varies dramatically according to age, population, body site and—especia...