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Fast 800 Calorie

If you’re looking for rapid weight loss, Stage 1 of the Fast 800 Calorie Diet should deliver the results you’re looking for.  This diet advocates 800 calories per day for a period of at least 2 weeks.  Continue for up to 8 weeks if you’re looking to lose a lot of weight or want more significant results.

The calorie restriction is ketogenic in nature and aims to burn fat yet retain muscle mass.  Aside from weight loss, the intention is also to trigger a range of positive metabolic changes (such as better blood sugar) to improve your overall health.

When you’re ready for Stage 2 of the diet, move over to our 5.2 Diet page and select the package that best suits you.

To learn more about the background, the benefits and research behind this diet, see our blog post The New Fast 800 Calorie Diet from Michael Mosley.

* Note that in all our Fast 800 menus we aim to get as close to 800 calories per day but there will be some small daily variations (+/-).

Exercising: read more here about exercising while on The Fast 800 Diet