Re: Misogi - The diet part
I don't really know if it only works in the short term, but a diet that basically allows you to eat as much as you want as long as it's meat, veg, seeds, nuts, tubers and fruits, has quite a decent variety for you to choose from. Eliminating carbs from wheat is the mainstay and they argue that for thousands and thousands of year, man lived as a hunter gatherer and we it would be more natural for us to eat like that. It is only fairly recently in the human timeline of existence that we actually increase our dependancy on grain.
I won't argue on on how agriculture created modern civilization nor would I argue that grain centric diet has been proven to be the main reason for increased obesity in America... But I would argue that modern grains (the same with modern meat farming) are producing food which is basically not as healthy as it could be for men. I see the modern grain as similar to the special food we stuff our cows with. Something to fatten em quickly.
Remember producing good food was expensive. And it was during the war that corn syrup made it's greates impact. A cheap food resource in terms of dollars per calory ratio.