Can someone please tell me if this is fat or loose skin? (photo)

70% fat, 30%skin laxity. I would recommend either lipo or Coolsculpting to reduce the fat. Your skin might tighten enough that it doesn't jiggle. Good luck.

Looking at your photos, it appears that is a bit of both, but I think it's the loose skin that's the issue. A tummy tuck would likely best help. Liposuction could also be done, but the skin tightening will depend on how elastic your skin is. Judging by your photos and dramatic weight loss (congrats!) liposuction may not be your best option. 

Correct me if I am wrong, but it appears that you have had a tummy tuck in the past. After as much weight loss as you have had, it is not uncommon that the poor skin elasticity results in some recurrent laxity even it the face of a tight closure at the time of surgery. 

If the skin jiggling is  the issue, I don't think liposuction is likely to improve the situation. The contour at rest looks quite good, and that is the usual goal of a TT. 

If you feel something needs to be done, it will be a TT revision. All the best. 

You have both loose skin and fat.  The  relapse and residual skin laxity is most likely a result of your signficant weight loss.  Weight loss patients can have relapse of their skin laxity after a procedure as a result of the extreme weight change and changes in collagen.  Repeat operation with removal of additional tissue is sometimes necessary in severe cases. It is a consequence of your biology and physical findings and not the procedure.  Whether you pursue an additional procedure depends on how much correction you desire.  All the best! 

I think it is a combination of both, given your weight loss but only an exam can elucidate this. I would not anticipate that your skin will contract sufficiently with lipo alone and this is obviously a major consideration given your profession.