Have I lost my smooth jawline due to fat or lax skin? (Photo)

Liposuction is frequently utilized to eliminate a "double chin" and/or help sculpt a jawline.  However, your issue is skin laxity which is best addressed with surgical tightening of the neck muscles and neck skin (i.e. a necklift +/- a full facelift). Glad to help.

      The neck is probably better addressed with a neck lift or a lower face and neck lift in this case.Kenneth Hughes, MDLos Angeles, CA