You may find this article on food combining of interest too. It give the history of how the idea began in the early 1900 and how it has subsequently has been dismissed with better understanding on how food is actually digested in the stomach.
Here is another article from two nutritionist at the University of UH-Manoa, Hawaii. And Dr. Stephen Barret at Quack Watch gives a detailed history of notion of food combining within the broader context of the theory of "Natural Hygiene". He says "Shelton taught that the following combinations are indigestible: "acids" and starches; proteins and starches; acids and proteins; fats and proteins; sugars and proteins; sugars and starches (note that Shelton classified sweet fruits as starches); melons and anything other than fresh fruit; and even two different proteins. Such pronouncements were debunked more than 70 years ago in both scientific and popular literature".
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