I'm on Day 5 and have occasional nausea, minor back pain and diminished urine output. I can only drink slowly and that seems to be all I'm doing. Don't ask how much, I know I should track it. Lets' just say it's all I can get in.

Now, my question is do our bodies require more liquid than before surgery. I've never been good at drinking enough, unless it's really hot outside....I'm in Ohio....so that's not happening!

I'm just curious about why we can become dehydrated so quickly now.

I'm no physician, but I think we need more because we are burning fat and the chemical reaction requires more Water than we used to drink. We also need more to flush out the waste products from the fat-burning (ketones) and to help the little residue from our low-cal diets in our diets from hardening in the bowel.

Edited to say that I asked my NUT today and her answer was the same as the above PLUS that our stomachs are so small now that if we become dehydrated we can't get in enough fluids quickly enough to replace what was lost. She said that presurgery stomachs could hold a quart of Fluid and now maybe 4 oz.. I said that fluids go right through my stomach but she insisted that we have to avoid dehydration because we can't replace fluids as we could pre-surgery.

I don't think we really need more. We just to be more vigilant about getting in fluids due to diminished stomach capacity. I found this on the Mayo Clinic website and it sounds comparable to what sleevers are recommended to drink:

Every day you lose Water through your breath, perspiration, urine and bowel movements. For your body to function properly, you must replenish its water supply by consuming beverages and foods that contain water.

So how much water does the average, healthy adult living in a temperate climate need? In general, doctors recommend 8 or 9 cups. Here are the most common ways of calculating that amount:

• Replacement approach. The average urine output for adults is about 1.5 liters (6.3 cups) a day. You lose close to an additional liter (about 4 cups) of water a day through breathing, sweating and bowel movements. food usually accounts for 20 percent of your total Fluid intake, so if you consume 2 liters of water or other beverages a day (a little more than 8 cups) along with your normal diet, you will typically replace your lost fluids.
• Eight 8-ounce glasses of water a day. Another approach to water intake is the "8 x 8 rule" — drink eight 8-ounce glasses of water a day (about 1.9 liters). The rule could also be stated, "Drink eight 8-ounce glasses of fluid a day," as all fluids count toward the daily total. Although the approach really isn't supported by scientific evidence, many people use this easy-to-remember rule as a guideline for how much water and other fluids to drink.
• Dietary recommendations. The Institute of Medicine advises that men consume roughly 3 liters (about 13 cups) of total beverages a day and women consume 2.2 liters (about 9 cups) of total beverages a day.

For many of us, it is very difficult to get in 60+ oz of fluids in the early days postop. You will really just have to force it down all day until your sleeve relaxes a bit and lets you drink more than baby sips. I got slightly dehyrated in my second week postop because it hurt so much to drink anything. But, after that bad experience, I started keeping a bottle of something in my hand or close by at all times. Gatorade worked better for me in that phase.

It will get better. Just stick with it.