Sticking with the same hair‑washing routine for decades may feel intuitive — but experts say it’s one of the most common mistakes people make as they age. That’s because both the scalp and the hair itself undergo significant physical changes over time, affecting everything from oil production to strength and sensitivity. “As we age, the scalp and hair undergo fundamental biological changes,” Dr. Alan Bauman, founder of Bauman Medical, a hair restoration practice, told Newsweek. “Keeping the