Intermittent fasting alternates a fasting period with an eating window. In 16/8, the most popular method, you eat within 8 hours (for example from 12pm to 8pm) and fast for the remaining 16 hours, sleep included. The aim is not to eat less for the sake of it, but to concentrate your meals so the body draws on its reserves between eating periods.
Getting started
Start gently with 14/10, then lengthen the fast gradually. Keep your meals balanced and sufficient during your window: fasting does not excuse you from meeting your calorie needs and your protein needs. To find out more, read our diet guides.
Frequently asked questions
Which fasting method should a beginner start with?
14/10 or 16/8 are ideal to begin with: they are easy to fit in (you often just need to skip breakfast or dinner) and well tolerated. The 18/6 and 20/4 formats are for experienced practitioners.
What can I have during the fast?
Only calorie-free drinks: water, sparkling water, tea, herbal teas and black coffee (no sugar or milk). Any calorie intake breaks the fast.
Does intermittent fasting make you lose weight?
It mainly helps by making a natural calorie deficit easier (fewer chances to eat). Without watching the quality and quantity of meals in your window, weight loss is not automatic. It is not suitable for everyone (seek medical advice if you have a medical condition, are pregnant or have a history of eating disorders).
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