1. Department of Nutritional Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan;
2. Bioscience Laboratories, Meiji Seika Kaisha, Limited, Sakado-city, Saitama 350-0289, Japan; and
3. Institute for Preventive Medicine, Nutrition and Cancer, Folkhälsan Research Center, Division of Clinical Chemistry, University of Helsinki, PB 60 FIN-00014, Helsinki, Finland