to be honest, i didnt completly stick to the pre-op diet.
i talked to several people who said that they cheated and it was ok. the doctors tell you its to shrink your liver, but the main purpose is to get you're stomach to shrink so you won't struggle as much on the post-op liquid stage.
i stuck to the pre-op diet 90% of the time. I went out one night and had a bit too much alcohol, and i added some carrots and potato with my vegetables sometimes and had some low fat crackers a few times. My surgery went fine, I had no problems.
As long as you stay away from fatty foods you should be fine :)
all the best!

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