Why is 16 hours the magic number for fasting?

The 16-hour fasting period allows your body to enter a state of ketosis, which starts burning fat for energy instead of glucose ( 18 ). This time frame is manageable for most people and aligns with the natural overnight fast while sleeping.

Does intermittent fasting work without exercise?

Yes, intermittent fasting can still help with weight loss and other health benefits without exercise by reducing calorie intake and improving insulin sensitivity ( 19 ). However, combining it with regular physical activity enhances results and supports overall health.

Does lemon water break a fast?

Drinking lemon water does not generally break a fast if it contains no added sugar or calories. The trace calories from lemon juice are minimal and unlikely to affect the fasting state.

How long should I fast to lose belly fat?

To lose belly fat, consistent daily fasting periods, such as 16-hour fasts (16/8 method), can be effective over time when paired with a healthy diet. Sustainable weight loss depends more on calorie balance and nutrient quality ( 20 ) than the duration of fasting alone.