I know that supposedly you shouldn’t try to LOSE more than about 2 lb per week on a safe and healthy weight-loss plan, and I also know that on some diets (e.g., Atkins and South Beach) you can lose quite a bit of weight very quickly by following the “induction” phase rules, or whatever.
My question is, can you gain weight more quickly than you lose it? Or, just how quickly can you gain weight, anyway? What’s the fastest a person could reasonably expect to gain weight? Does it vary by body type and metabolism? (what is “metabolism”, anyway?) Does it depend on what you’re eating and on the type or amount of activity you’re getting? If I went on the “sit on my butt on the couch and eat Fritos” diet, would I gain 5 pounds a week? 10 pounds? What’s the upper limit we’re talking here?