The Beverly Hills Diet--in case anyone doesn't know--is a six-week unbalanced diet that attributes special power to fruits and to food combinations; Mazel's follow-up plan is slightly less extreme nutritionally, but no less complicated. How wonderful, we first hear, that the BDH caught on (""there were riots over ripe bananas in mid-Manhattan, and caches of watermelon were hidden in lower desk drawers on Capitol Hill""). Then Mazel reviews ""Conscious Combining""--eating foods together that ""digest together best."" So: fruits go alone; fats go with ""other proteins"" or carbohydrates; carbohydrates go with other carbs and fats; proteins go with other proteins and fats; and proteins and carbohydrates fight one another, digestively speaking. To explain how this rigamarole can make you thin, Mazel uses code words like ""Debilitating Fat Consciousness"" (as in ""even my DFC was ever lurking and had almost knocked me off my pineapple""), along with lists and lists of rules (""a protein day should be divided into only two eating experiences""); in support, she also offers written think-thin exercises and some recipes. Criticisms of the regimen remain: mainly, it can be too low in protein; and some adherents lose weight through the severe diarrhea they experience. Though a physician's introduction proposes that the plan is okay because we have no evidence to the contrary, this is no diet for a lifetime. It's chancy even on a short-term basis.