A 21-day so-called "diet" of grapefruits, a little protein and not much else.
Despite many ludicrous claims, grapefruit (like cabbage) does not possess any "fat-burning" properties.
What you eat
Half a grapefruit & black coffee.
Half a grapefruit, 1 egg, some salad, a piece of dry toast & tea or coffee (no milk).
Half a grapefruit, 2 eggs, half a head of lettuce with tomato, & tea or coffee (no milk).
Grapefruit is fat free, low in calories and full of vitamin C. Pink grapefruits also contain some beta-carotene. However, eating a few grapefruits hardly justifies calling it a "diet".
Lacking sufficient iron, calcium, and many vitamins, this "diet" is unhealthy as well as monotonous. Also, it contains far too few calories. Needless to say, it doesn`t help you to change your eating habits which is the No 1 secret of permanent weight loss.