Going back to your original question. If you go and have a pizza then you will kick your body out of the fat burning mode and it will take a couple of days of good low carbing to get your body back on track. You will certainly see a weight increase, albeit water weight. The choice is yours. This will not effect your cholestorel levels provided you go back low carbing afterwards.

The choice is yours, however others have already given you some alternative suggestions to your dilemma.