0.5kg a week is not rapid weightloss, nor is it extreme. That's a 550 calorie deficit, which is less than two candy bars worth of calories (an 80g candy bar has

0.5kg a week is not rapid weightloss, nor is it extreme. That's a 550 calorie deficit, which is less than two candy bars worth of calories (an 80g candy bar has 300-400 calories).