Dr. Hay, Dr. Jackson and then actually the entire medical science world by 1850's all proved proper diet.
God's Laws are real on earth----each specie supplied proper diet for free---humans no exception. The Dr. Hay book I call BOOK 1 explains it best. In the back of his book his nurses / staff wrote an alternative diet, but Dr. Hay believed in the mono fruit diet. Dr. Jackson explored a diet for where he lived in Toronto and he is actually my favorite of all authors, but the Dr. Hay book saved my life.
Dr. Christopher explains the Fig Tree diet---living under your own fig tree with what you can grow your self-------it falls short, because we are born fruitairians.
Naturally no human obeys, so we all suffer with parasites and premature death.