Sacha Baron Cohen -- Good Genes or Good Docs?!

Sacha Baron Cohen is looking very nice!

Here is a 30-year-old version of the English actor, known for his famed characters like Ali G and Borat, looking scruffy at an event back in 2001 (left).

And, 18 years later ... the now 48-year-old comedian and husband to actress Isla Fischer -- who is celebrating his birthday Sunday -- showing off his slicked-back hair and good looks after the great success of his television series "Who Is America?" at a Press Conference for "The Spy" in Beverly Hills back in August (right).

Woah, Woah, Wee Wah!

The question is ...