Fasting for a day causes initial weight loss from water stored in muscles when glycogen is used for energy. About 3-4 grams of water are lost.
Not drinking water can lead to dehydration and temporary weight loss, but it is not true fat loss.
As your body uses up glycogen, you may lose about 1 to 2 pounds of water weight. But once the glycogen is depleted, the weight loss slows down.
While fasting for one day can cause some weight loss, significant fat burning doesn’t begin until after 12-16 hours of fasting.
If your body runs out of glycogen, it may start breaking down muscle for energy, which can contribute to weight loss
In total, depending on your body type and activity level, it’s possible to lose between 1 to 3 pounds in one day without eating
Fasting for a day slows metabolism and conserves energy, leading to slower fat burning in the long run.
As you lose weight from not eating, your energy levels can drastically decrease, making you feel sluggish and weak.