1. Institute for Preventive Medicine, Nutrition and Cancer, Folkhälsan Research Center, and Department of Clinical Chemistry, University of Helsinki, Biomedicum, P.O. Box 63, 00014 Helsinki, Finland, Research Institute of Public Health, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland, Central Research Laboratories, Yomeishu Seizo Company, Ltd., 2132-37 Naka-Minowa, Minowa-cho, 339-4601 Nagano, Japan, and Department of Pharmacognosy, Faculty of Pharmaceutical Sciences, Health Sciences University...