If you are going to pick a small arbitrary region of the country to compare, then Iām sure you could pick an arbitrary region of Japan to compare to New Jersey favorably.
This is a very fair point but at the same time it there are one-million asians in New Jersey (mostly non-Japanese) and the link states that the pattern is true for lots of big states such as NJ, MA, NY, PA,etc. I agree there are probably cities in Japan or certain areas that have extra high life expectancy too but I think this cuts against the diet argument a bit.
On a recent Tyler Cowen podcast he stated that Japanese Americans have the longest life expectancy and speculated it was a combination of genetics + wealth. I think it is a good counter to the diet argument the piece puts forward. I was unable to find a link to the study he referred to though - so I linked to the one above. Hopefully my recall of Cowen's point is correct.