The "science" behind the liver shrinking diet.

I know why we need to shrink our Liver prior to surgery. What I am looking for is why is it a "liquid" diet, and why am I allowed to have carbs such as oatmeal, grits, and cream of wheat? Is the main focus to cut out sugars and fats? What specific foods are we trying to stay away from? I am not trying to find a way to "cheat" the diet, just my logical brain trying to find a method to the madness.

There are arguments that the liver doesn't even shrink much during these attempts.  The purpose is said to make it easier for tools to maneuver around the liver to perform the surgery.  If the surgery was open instead of lap, it shouldn't be necessary at all.  If a surgeon was more confident in his ability with the tools, it shouldn't be necessary either.

my dr didnt have me do a liquid diet before surgery, i had to do a low carb diet for 2 weeks. My surgeon was unavailable on my surgery day, and it was pushed for another 2 weeks. So I didnt have carbs for 4 weeks before surgery.

Liquid diet sounds worse.

Julie, my doctor put me on a 20 carb/day 4 weeks prior to my surgery.  (I am scheduled for the sleeve on 01/26/16).  I am trying to understand HOW to get my carbs down to 20/day since EVERYTHING has carbs!  Can you share some foods that you were able to eat during your 4 weeks before surgery??

i mainly stuck to protein and green veggies ^^ lots of tuna and chicken basically :P if I got hungry before a meal I would have cheese for a snack.

Look at the Atkins/Keto sights. Before my surgery, I lost 32 pounds on Atkins Induction.

My meals looked like:

Breakfast-- Mushroom/Onion omelet with Swiss cheese

Lunch-- Turkey burger wrapped with lettuce (mayo, mustard, red onion, tomato)

Dinner--Salad including red onion, tomato, mushrooms, sunflower seeds and topped with thin cuts of New York Steak and homemade Bleu Cheese dressing. Sauteed veggies and "Fauxtatoes" (aka creamed cauliflower).

Notice what's missing. CARBS! No bread. No sugar. No processed foods. And I still ate like a Queen! 

Send me an email if you have any questions. Once you get the hang of it, you'll have no problems.

There's nothing magical about using liquids for some weight loss immediately pre op, other than that they're premeasured low calorie portions. Some people find premeasured liquids easier than dealing with their nemesis (food) and it's also a way to get your head in the game for early post op healing. 

Maybe I should clarify my question. What foods that are eliminated while on this liquid diet, are what causes the "shrinkage"?

Thank you everyone that have responded so far. I love how helpful everyone is on here.

Our livers carry lots of fat, so the concept is weight loss leads to fat reduction on the liver. The smaller the liver, the easier it is to move during the surgery. So it's the weight/fat loss that matters. Calorie reduction is the way to accomplish that, so it has nothing to do with particular foods, only about the number of calories you eat.

Theoretically, you could eat nothing but candy ... as long as you had adequate calorie reduction to lose weight.  But of course the problem with that approach is you'd be really hungry.  And protein is the Nutritional building block your body requires and offers higher satiety so that's why many programs point you to protein calories for weight loss pre and post op  

Hope that helps. 

Thank you Spencerella! That is an explanation that makes since to me.