Kate Hudson -- Good Genes or Good Docs?!

Kate Hudson's good looks are truly timeless!

Here's a 20-year-old version of the "How To Lose a Guy in 10 Days" actress radiating with youth at a movie premiere for "200 Cigarettes," one of her new films at the time, in Los Angeles, California back in 1999 (left) and 20 years later ... The multitalented star and mother of three -- Who celebrated her 40th birthday this past week -- was spotted on the red carpet looking better than ever showing off her hot post-baby bod at an award show last month in Beverly Hills, California (right).

Talk about being "A Little Bit of Heaven."

The question is ...