Happy birthday in advance! Not looking to give you any advice on what to do or not to do, just sharing my fairly recent birthday/cheat day experience.

I was really looking forward to my birthday since I hadn't eaten any pizza in months. I really love pizza. On top of that, I baked (what I thought to be) a super delicious birthday cake for me and my family the day before.

Anyway, I ended up eating a lot of cheese and crackers and fruit that day, plus a huge pizza and a large slice of that birthday cake later in the evening. Everything felt right with the world again. Cheat day, way to go. ^Right?

To spare you any nasty details, I spent the following hour on the toilet in crippling pain. And on top of that, I was sweating, I was cold, I felt like I had been kicked in the stomach repeatedly and left to die on the side of the road on a horrible January morning. Maybe my body had forgotten what it was like to digest huge amounts of food. Maybe I ate everything too quickly. Maybe I made unfortunate food combinations. No idea. But looking back, I really shouldn't have done that.

I was about 3 lbs heavier the following day, but most of that was just water and poop. I ate 300 cals less for the rest of the week and it all went back to normal within 4 or 5 days, I'd say.