First there is no wonder diet as such. The basic  principle  behind every diet is to create a negative calorie  balance i.e to eat a bit lesser than what  your calorie intake should be as per RDA ( recomended daily allowance ) for calories as per your age, sex and activity level.

The mathematics is that  if  you create a deficit of 1000 kcal then you  lose @ 1kg  per week and 1/2 a Kg if the deficit is 500 Kcal. This deficit can  come  through diet planning  or through exercising your  body  over and above  your  routine activities.

This mathematical equation works  for starters very well. But as the time period of calorie cutting becomes over 3 months - 6 months there is a slower loss of weight.  Reason being the body adaptats to  lesser calories  by consuming  lesser calories for basal  body functions like respiration, circulation, digestio etc. This is called  astage of lower basal metabolic rate. So the calorie  deficit being same  does not work as efficiently as there is a lesser support from the  body in  burning the calories. Hence come the irritable plateau in weight loss. It  is here that  one is attracted towards 'wonder diets' which are basically further  low in calories and also  compromise on essential  nutrients. But  how  do they work?? Or don't they?More about these diets in the  next  post...