Jay Cutler Lets the Chest Hair Out In Mexico (PHOTOS)

Jay Cutler -- party guy?!?!?!

The Chicago Bears QB seems to be loosening up and having some fun on his wife's 30th birthday vacation to Mexico ... even taking a half-open shirt pic with Kristin Cavallari's hairstylist, Scotty Cunha.

Kristin made a cheeky comment about Jay's shirt on Instagram saying, "Hangs out with the gays once."

FYI, Scotty is kind of a big deal in the beauty world ... he's also part of the Kardashian glam squad.

The gang is currently hangin' in Punta Mita ... boozin' and beachin'.

Enjoy!