Proper nutrition is,"" says Berger (of Southampton Diet fame), ""essential to proper immune function."" So far so good. But then he raises the problem of ""hidden Food allergies,"" many of which are caused by mainstays of the modern American diet such as (in order of frequency) cow's milk and wheat products, yeast, eggs, corn and soy products and cane sugar. Then he details how to self-test for allergies to ""the sinister seven"" and other foods, and then how to design menus with that knowledge in mind. His regimen involves a 21 -day rotation diet that totally eliminates the seven culprits and also never repeats the same food more than once every four days. By this means, one may be able to pinpoint other less-common allergenic foods. Then, by means of a 14-day ""reintroduction plan,"" the seven targeted foods are added and removed one by one. An allergic reaction targets individual foods and alerts one either to eschew them entirely or consume them less. Berger's approach will appeal to highly disciplined do-it-yourselvers capable of abstaining for an extended period of time. But, even those who prefer lo be tested for food allergies by a physician, will find his well-balanced, high-carbohydrate, high-fiber. low-fat menus helpful in designing meals that are optimally nutritious as well as minimally allergenic.