Why is the diet on peritoneal is more liberal
than in hemodialysis.

With peritoneal, you're doing 4 or 5 treatments a day, and when you weigh yourself each day, you can decide what strength solutions to use based on how much fluid you have on. Nothing has much of a chance to build up when you're flushing your peritoneal cavity every four hours. It's not like hemo, where you go an entire day with no dialysis-- that's why hemo patients have to be more controlled about what they eat and drink.