Alan Thicke -- Good Genes or Good Docs?

Growing older is anything but a pain for Alan Thicke!

Here’s a 38-year-old version of the "Growing Pains" television dad at an awards ceremony in Los Angeles back in 1985 (left) and 31 years later ... the 69-year-old father of three at a golf tournament last month (right).

"The best is ready to begin."

The question is...