I used to need over 9 hours of sleep, preferably 10. Now in my late 20s I make do with 7-8 hours with some impact on mental sharpness and likely physical health

I used to need over 9 hours of sleep, preferably 10. Now in my late 20s I make do with 7-8 hours with some impact on mental sharpness and likely physical health as well but otherwise able to function. Does wonders for my work life balance since I actually have time in the evening for hobbies / activities / relaxing.