A If a patient already reached a stable weight, then he can be a good candidate for a tummy tuck. However, if someone is still ACTIVELY losing weight, then he has to wait until it stabilizes at least around six(6) months before he may proceed with the procedure. Otherwise, if he keeps losing weight and does the tummy tuck, there is a greater chance that he will have more laxity in the future.
Make sure to consult a board-certified plastic surgeon if you wish to proceed with the procedure.
I hope this helps.
Know why an Awake Tummy Tuck is a much better option than a mere tummy tuck: