Fasting, which is drinking only water without consuming food for a long period of time, is an extreme practice with potential health risks. If you are considering water fasting or fasting, always do it under the guidance of a medical professional. Here is some general information about water fasting: 1. **Short-term water fasting**: - **Duration**: Generally, healthy adults without major health problems can do water fasts for 24 hours to several days (usually no more than 72 hours) under medical supervision. - **Effects**: Short-term fasting may help clean the intestines, lose weight, or conduct spiritual retreats, but scientific evidence to support this is limited. 2. **Long-term water fasting**: - **Risks**: Water fasting for more than a few days may cause serious health problems, including malnutrition, electrolyte imbalance, decreased immune function, muscle loss, etc. - **Survival limit**: In extreme cases, there are records of people surviving on water alone for several weeks, but this is usually accompanied by serious health risks and is not recommended. 3. **Precautions**: - **Individual differences**: Everyone's physical condition, basic health and tolerance are different, so the effects and risks of fasting will also vary. - **Potential symptoms**: Symptoms such as dizziness, fatigue, headache, and hypoglycemia may occur, which may be life-threatening in severe cases. - **Special populations**: Pregnant women, breastfeeding women, and people with chronic diseases (such as diabetes and heart disease) are not suitable for long-term water fasting. 4. **Recommendations**: - **Consult a professional**: Before considering any form of fasting, it is recommended to consult a doctor or nutritionist to ensure safety. - **Gradual adjustment**: If the purpose is to lose weight or adjust eating habits, consider a gentler diet adjustment method, such as intermittent fasting, rather than drinking only water for a long time. In short, although short-term water fasting may be feasible in specific circumstances, long-term skipping meals and drinking only water poses significant risks to health. It is strongly recommended to be carried out under professional guidance and carefully evaluate its necessity and potential impact.