how muscular you are.Д¬alculating your BMI before starting 5:2 or The Dirty DietвЂ“ and then on a regular basis after that вЂ“ will show your progress. ItвЂ™s a useful guideline but does have limitations, as it doesnвЂ™t recognise lean mass i.e. ItвЂ™s alsoВ helpful if youвЂ™re fasting but not losing weightВ вЂ“ use your TDEE to check youвЂ™re not consistently over-eating on your non-fasting days, which could undo the good work on fasting days.ДЇor much more about enjoying your food andВ losing weight, readВ theВ 5:2 Books, which all explainВ how to balance your eating habits.Д«MI - Body Mass Index - is a basic calculation of whether you are a healthy weight or not (18-25 is the number you are aiming for вЂ“ lower, and you are underweight, higher and you may be running a health risk by being overweight or obese). Most people use their TDEE as a guideline we naturally eat less on some days, and more on others. ThatВ doesnвЂ™t mean calorie-counting every day, unless you really want to.

It gives youВ a guideline for how many calories you can eat on non-fasting days without gaining weight: by also fasting twice a week, you will create a calorie deficit/shortfall, so you lose weight. ItвЂ™s simply a guideline вЂ“ if you exceed it by up to 10%/50 calories, you should still lose weight! For most of us, this will be fairly close to 500 for women/600 for men. THEN divide by 4 to get a personalised fast day guideline. To work out your Fast Day Limit: simply use the calculator below to work out your estimated вЂtotal daily energy expenditureвЂ™. By eating at around that level 5 days a week вЂ“ and then fasting for 2 вЂ“ youвЂ™re creating a calorie deficit вЂ“ or shortfall вЂ“ which means your body has to burn fat for energy - so you lose weight. Your TDEE or Total Daily Energy Expenditure is how many calories you need each day to maintain your current weight. I donвЂ™t recommend calorie-counting every day вЂ“ but knowing your BMI and your TDEE (Total Daily Energy Expenditure) helps give you a guideline and track progress.

Using these calculators will also help you understand how much you can eat on a non-fast/normal day without undoing your hard work on a fast day. The 5:2 fast day limits of 500 or 600 calories on a Fast Day are based on eating a quarter or 25% of what the вЂaverageвЂ™ woman or man needs to eat to keep their weight stable - but how many of us are вЂaverageвЂ™? Being taller, shorter, heavier or more/less active than average will affect how many calories you need. Knowing your TDEE/personal energy вЂneedвЂ™ helps you understand what your body needs to maintain weight вЂ“ and why you gain or lose.

Caloric deficit calculator