Mongolian spots fade by age 6–7
Mongolian spots, bluish-gray birthmarks common in African, Asian, and Hispanic children, usually fade by ages 6–7 and can be mistaken for bruises.
Snapshot · Stuff You Should Know
Selects: Birthmarks: Probably Not the Mark of the Devil
Explore episode
Jun 20, 2026
Where this was said
Café au Lait and Neurofibromatosis
At 28:15 · chapter starts 26:00
After the lengthy coffee-and-sushi tangent, Josh zeroes back in on the medical significance of café au lait spots. As standalone marks, they're harmless and can appear anywhere on the body with no pattern. But having 6 or more — especially if they're dime-sized or larger in an older child — can indicate neurofibromatosis type 1 (NF1), a nerve condition [1] — Josh Clark "Café au lait birthmarks — light brown spots that can appear anywhere on the body — are usually harmless. But having 6 or more, especially l…" 26:00 . Josh is careful not to catastrophize: NF1 can be asymptomatic, and the café au lait spots alone don't confirm a diagnosis. But it's one of those cases, like port wine stains and Sturge-Weber, where a birthmark is a potential symptom of something deeper worth investigating.
Café au Lait Spots and the 6-Mole Warning
Café au lait birthmarks — light brown spots that can appear anywhere on the body — are usually harmless. But having 6 or more, especially larger than a dime, may indicate neurofibromatosis (NF1), a nerve condition. It's not a death sentence, but it is a sign to see a doctor.
Café au lait & neurofibromatosis
Having 6 or more café au lait birthmarks — especially if larger than a dime — may indicate neurofibromatosis (NF1), a nerve condition that warrants a doctor visit.
Mongolian Spots: Birthmarks Mistaken for Abuse
Mongolian spots are deep-pigment birthmarks common in African, Asian, and Hispanic babies that appear as bluish-gray patches on the lower back and buttocks. They're easily mistaken for bruising and typically fade by ages 6–7.
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