The composition of herring-roe powder used in this study is
given in Table 1. Herring-roe was fished in Sitka, Alaska, USA. The
test meal was prepared by freeze-drying in a conventional method.
The production and packing was performed at Ihara Suisan Co., Ltd.
(FM96883/ISO9001 certification).
The subjects were instructed to ingest 15 g per day of herring-roe
lyophilized powder (herring-roe powder) (containing DHA 540 mg
and EPA 300 mg) or a placebo powder (11 g of unpolished rice
powder containing 4 g of soybean curd used to imitate the texture
and appearance of herring-roe powder) in two parts per day.