There is an old saying that when you eat eel on "Doyo no Ushi" Day (18 days before the first day of autumn, on the day of the Ox, from the 12 symbols of the Chinese zodiac), then you won't suffer from natsu-bate."〔【出典】『これが分かれば日本通』(田仲邦子著)◆【出版社】株式会社ヤック企画 〕"YA03-091", "2518157"
There are some annual events related to this calendar. For example, people eat eel on the day of the ox in mid-summer to recover from fatigue."A0000277", "2517050"
真夏の土用の丑の日が7月24日にやって来る。
The day of the ox in midsummer is coming on July 24.〔【出典】Catch a Wave, 2008年6月27日号◆【出版社】株式会社浜島書店 〕