Dr. Atkins' Diet Revolution, published two decades ago, sold millions of copies but was denounced by medical authorities for its unsound high-calorie, low-carbohydrate regimen. Now it's back, slightly modified, and billed even more contrariwise as a high-fat, low-carbohydrate diet. Atkins blames carbohydrates for most cases of overweight--as well as for much fatigue, mental fog, high blood pressure, high cholesterol, heart disease, diabetes, and cancer. A high-fat diet, he says, is harmful only when added to a high- carbohydrate diet. At times, he backs off and hedges, admitting, for example, that refined flour and sugar, not all carbohydrates, are the culprits, and even that the desserts he promotes should be limited to special occasions. Still, heavy cream, butter, and cheese abound in his recipes; bacon and eggs are on his daily breakfast menu; and his program, especially the 14-day ``induction diet'' designed to induce ketosis, or fat-burning, turns all prevailing guidelines upside down. It will be interesting to see how this book does now that low-fat, high-carbohydrate eating has been so widely accepted by professionals and public alike. Atkins claims success with his 25,000 overweight patients (who take an average of 30 nutritional pills a day along with the diet), and he scores a point or two against pro-establishment preconceptions among researchers, but he certainly doesn't prove that his is the healthier diet. Still, get ready for a blitz.