I would just thank them for the compliment. I am not Asain, I am 47, petite, 5'5" size 2 and look young for my age (except for my boobs). I'm of Native American heritage so I have long straight dark hair. Thanks to hormone patch my boobs are oversized for my body but I am not complaining.
My husband is just 52, Italian, great skin, good shape with salt and pepper hair. I am often mistaken as his daughter. Of course this makes his skin crawl.
My 14 yr old daughter has friends who say I am too young to have a 14 yr old. They think I am in my 20's and I do get mistaken for a student often when I am at the school.
ENJOY it!! It won't last forever!!