16/8 is the best intermittent fasting window to lose belly fat according to the experts and this is the most popular method also 

If you find it challenging to fast for 16 hours, you can start with the 12-6-6 method and gradually increase the fasting window 

If you are a beginner, you have to start intermittent fasting in a 12-6-6 formula 

When you feel that you can easily apply and follow this 12-6-6 formula, then the time comes for you to intensify it 

For that, you need to use a second formula which is the 16-8 formula 

This type of intermittent fasting is a little intense, and this is why you should only follow this when you can easily follow the 12-6-6 formula 

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