This section of the book is from the "Handbook of Nature Cure Volume One: Nature Cure vs. Medical Science" book, by John L. Fielder.
"Health Foods" appear to many people to be in the same category as herbs but, although there are some borderline cases, in the main there is a clear distinction. Herbs are plant tissues which have a poisonous effect on the body, whereas the typical "health food" is most often a concentrate or extract of a non-poisonous nature. "Health foods" which, for instance, induce bowel movement, are of the borderline type. They act either by chemical or physical irritation of the intestines. (See "Two Health Problems"). But the majority of "health foods" are relatively innocent substances, which may to some extent make good one or other of the all-too-common deficiencies of civilised dietaries.