Im 54, and right now Im 130lbs.  I had a baby six months ago, so my hips are still wider than normal.  I cant do tight clothes right now since Im still working on the belly a bit, so I sized up to a Large.  Its soft and comfy, and fits pretty good... mostly fitted but not tight... its just barely loose enough in all the right spots, and the length enables me to bunch it up a bit to hide belly flab. I really like the thickness, the quality, and the length of this tank, so I ordered it in another color the day I received it.