really really really amazing post. Oh man what a life and experiences in Japan's farms. The good thing is that you learned a lot although you worked so much. haha when you think back try thinking the fact that you lost the extra weight :P
Also a thing i noticed was a crab :P what a crab does there? was there a river-sea anywhere near?

Finally i had made a post about wine a couple of days ago and while i was researching i came across the french paradox in which while as you said you were used to butter milk etc etc as the French diet and ways are you guys had low heart rates issues and that was considered to be due to wine. A thing scientists noticed now and use as arguments is that Japanese have even lower heart rate issues and they drink more beer than wine so the whole deal maybe in general the diet ( like you said again rice,vegetables, hard work)