1. Internal Medicine II, Showa‐ku, Nagoya 466 8550, Japan
2. Human Nutrition, Nagoya University School of Medicine, 65 Tsurumai‐cho, Showa‐ku, Nagoya 466 8550, Japan
3. School of Biological Sciences, University of Manchester, G.38 Stopford Building, Oxford Road, Manchester M13 9PT, UK