“When you don’t follow a keto diet, you consume a good amount of carbohydrates … so when you follow a keto diet one of the things that happens fairly quickly is that, because your glycogen stores are depleted, you lose water weight,” he says the registered dietitian Andy Bugatti (via member).
So when you stop doing keto, expect the weight of the water to return. “When carbohydrates are reintroduced, additional water is also introduced; 4 grams of water are obtained with each gram of carbohydrates,” says dietician Shoshana Pritzker Form. “This can make you feel like you’ve gained a ton of weight quickly, even though it’s probably largely water retention.”
But even if you stick to healthier, untreated carbohydrates, the swelling may come to haunt you. “The most common problem that people face is bloating and intestinal problems due to the reintroduction of fibrous foods,” says dietician Taylor Engelke; but as long as you stay in unrefined carbohydrates, the swelling should disappear from a few days to a few weeks.