Should I start my Pre-Op diet early?

I am getting anxious for my surgery, which is scheduled for 19 September.  I was considering starting my pre-op diet now, rather than waiting for 4 September.

I should note that I am currently at a BMI of 37.9, (67 inches, and 242 pounds), which is down from 39.15 (67 inches and 250 pounds) when I first contacted the surgeon.  If I continue to lose weight, is it possible that I could drop out of the BMI range necessary to qualify for the surgery?  I would hate to do all of the work to lose weight, knowing that I would just put it all back on like I have so many times before because my surgery was cancelled.

What do you guys think?

Rather depends on what it is. If you are simply doing a calorie controlled or similar diet, starting early means getting into good habits and more weight loss. Eating healthily cannot be bad! But if your pre-op diet is a drastic liquid only, very low calorie diet, just sounds like unnecessarily hard work and not all that healthy for a long period. 

i have no idea about the effect of a lower BMI on the surgeon's decision to operate. Why not ask your medical team?

If you have a date scheduled, I assume you've already received an approval letter from your insurance company. In which case, losing weight should NOT knock you out of getting surgery---but check to be sure.

As for a pre-op diet---like Kate said, you do NOT need to be on a drastic, liquid-only sort of diet. Right now, your body needs to be getting in the best possible shape for having surgery, and there's a lot more to that than just losing weight. You need to be building your protein stores, because you'll need that for healing. You should also get a pretty extensive set of labs drawn, and work on getting any low values well into the 'good' range. Eating a sensible, moderate-calorie, high-protein 'diet' is probably the best thing you can do to get ready for surgery.

Thank you for your reply.  I have a surgery date, but no insurance approval since I am self pay.  I am going to do the sensible diet that you recommend, and will go on the drastic one as scheduled.

since you are self pay,those requirements are not going to affect you in the same way they would if insurance was paying.

2.5 months pre-op I started swapping out meals I ate alone (breakfast and lunch most days) for protein shakes. This worked really well for me both for my mindset and my body. I lost 25 pounds - woo!  Of course then I didn't really lose a crazy amount of weight on the actual pre-op diet, since I had already shed those first 8-10 pounds people seem to lose when starting a diet, heh. No big deal.