I'm not a doctor, but I can provide some general information about water fasting.
The amount of weight you may lose during a 3-day water fast can vary depending on several factors, such as your starting weight, body composition, metabolism, and overall health.
During a water fast, your body primarily relies on stored glycogen (carbohydrate reserves) for energy. Glycogen is stored in your muscles and liver, and it requires water to be stored. As you deplete glycogen stores, your body also loses the associated water weight.
Additionally, your body may start breaking down stored fat for energy after the glycogen reserves are depleted. The initial weight loss during a water fast is primarily attributed to water weight. It's important to note that this weight loss is temporary and can be regained once you resume eating and replenish your glycogen stores. It's difficult to predict an exact amount of weight loss because it varies from person to person.
Some individuals may experience more significant weight loss during a short water fast, while others may experience less. It's also important to remember that weight loss should not be the sole focus when considering fasting, as there are potential risks and it may not be suitable for everyone.
If you're considering a water fast or any type of fasting, it's advisable to consult with a healthcare professional who can evaluate your specific circumstances and provide guidance tailored to your needs.