World Redhead Day 2026 spotlights red hair’s genetics and quirky facts

World Redhead Day on May 26 shines a light on red hair—with fewer than 2% of people having it and Scotland and Ireland as hotspots—while noting eight genes, including MC1R, influence red hair; the rare blue-eyed redhead combo occurs about 0.17%, redheads may require about 20% more anesthesia, produce more vitamin D, are often overrepresented in ads, and the hair color isn’t going extinct.