I’m still watching reruns of SG-1 and I’m a little behind, but, so far, she looks better than I do at a bit over 40. Granted, I have no idea how old she really is. (It was more of a general point about characters that don’t age or age slowly being played by actors who age normally. Angel, for example.)
Googled her just now.
Born 1965 according to one source.
And I think a lot of those racy Amanda Tapping “images” are photoshopped. ;^)