But what happens if Drew gains it all back? My faith would be crushed...
That's the tough part. I've lost 60-80 pounds at least 4-5 times in my life. But then life always seems to get in the way, old habits return, and the weight comes back.
FWIW, calorie restriction is the way to lose the weight, but exercise certainly helps you feel healthier and makes it easier to keep with the healthy eating. I've gone as low as 1200 calories a day, and that will certainly drop the pounds fast, but it's hard to keep at it. 1400-1700 calories a day seems to be the butter zone for me, where I lose a steady 8-10 pounds or so per month, and I am able to keep it going long term without feeling like I'm starving myself.
Lean protein has always been my staple when trying to lose weight. When you cut your calories way back, you still need to make sure you're getting enough protein. Chicken, egg whites, vegetarian options (Trader Joes Meatless Meatballs are great), etc. are all great ways to fill up and get protein while still keeping the calorie count low.