Fad Diets Often Produce Weight Loss, at Least Initially, Because

Fad diets often produce weight loss, at least initially, because they ____. ​

A) dictate the correct distribution of energy among the macronutrients
B) prevent rapid spikes and declines in blood glucose levels
C) don't require people to count kcalories, and are thus easier to stick to
D) are designed to limit energy intake to around 1200 kcalories per day