Poorly supported, muddled encouragement to reassess our eating habits--loosely based on the author's observations of the eating patterns of different ethnic groups. Weiner, who has a doctorate in Nutritional Ethnomedicine (Berkeley), urges that readers visit a nutritionist to help put their diets in order; but because nutrition is now like ""psychology when Freud first took his medical degree,"" we must participate by first understanding our backgrounds and the basics of nutrition, and being aware of common misconceptions. Fair enough, but Weiner doesn't organize any of this into useful form--and the biggest loss is his failure to bring together and concretely apply his knowledge of ethnic eating habits. In four ""books""--""Night Darkness,"" ""Dawn Light,"" ""Morning Brightness,"" ""Noon Clarity""--he wanders through such topics as diet and cancer, and ""Holistic Health: A Haven in Demise?"" Much of this is Weiner's own opinions, moreover, and is conjecture at best; the low point, undoubtedly, is a ""nutritional autopsy"" on Adele Davis, where Weiner tosses off in one page the suggestion (to be used as a caution against self-medication) that Davis may herself have induced her fatal bone marrow disease by overdosing with folic acid supplements. Not all is quite at this dismal level, but there's no solid help we can't get elsewhere, and the special point of view on ethnic diets is lost along the way.