T C Fry was indeed a heavyweight of NH and strongly influenced the Diamonds in popularizing this way of life. Very clever btw how they handled this by publishing a book on weightloss (which became an International bestseller) and the sequel which automatically became a bestseller as a result, on the principles of NH.
I agree with the summary of the NH diet as compared to the other diets listed, but a significant exclusion from the NH diet, and which was "discovered" by Dr Joel Fuhrman MD (a protege of Sheltons) is that Alpha-Linolenic Acid (Omega 3 family) whose sources include Flaxseeds (linseeds), Mustard seeds, Hemp seeds, Walnut oil, Green leafy vegetables, Grains, Spirulina, and their oils made from Linseed (flaxseeds), Rapeseed (canola), and Hemp seeds, although providing an abundance of ALA, the body is unable to convert this Omega3 by the body into sufficient DHA (docosahexaenoic acid) and EPA (eiocosapentaenoic acid) for the optimal health of the Brain, nervous system and eye health.
DHA comprises approx' 40% of the PUFAs (Polyunsaturated Fatty Acids)in the brain and 60% of the PUFAs in the retina; 50% of the weight of the neuron's plasma membrane is also composed of DHA.
Fuhrman reasoned that Shelton developed Parkinsons disease as a result of this deficiency in DHA, despite his strict and healthy diet.
The only guaranteed way of receiving enough DHA within the diet (and remain vegetarian) is to consume the only direct source of DHA from vegetarian sources: Algae, which is currently quite expensive in the supplement form.
This is the main reason I changed over from the traditional NH diet into one of including oily fish and later: organic chicken.