Stay healthy in summer with unagi

I've always known that unagi, eel, is a really popular food in Japan, particularly in summer. There is even a day for eating eel, called "Doyo no Ushi no hi", midsummer day of the Ox,which is on in July annually. (July 19th in 2025 I believe). What I didn't know, until I saw it on the TV this week, is that there is some scientific reasons behind it, not just an old wives tale or symbolic tradition. 

There is a saying on "Doyo no ushi no hi", 「丑の日にちなんで、“う”から始まる食べ物を食べると夏負けしない」I've liberally translated it into "Eat foods that start with the letter 'u' on Ox day and you won't succumb to the summer heat". Although the saying pertains to all foods that begin with the letter "u", unagi (eel) is the most popular. 

According to the TV Program, confirmed by a bit of online research, the vitamin B1 in unagi is the key. We lose more B1 through sweat in the summer and eel replenishes it as it is a food rich in Vitamin B1. But it is also packed with other vitamins and nutrients which help restore energy and provide the stamina needed to cope with the intense summer heat and humidity.

It is often pitched as having "cooling effects". While this may not be exactly true, there is no denying that it is nutritious and has essential vitamins needed to help survive the cruel summer. Do you eat eel in summer?