Edward Smith (physician)

As a general definition, it may be stated that a food is a substance which, when introduced into the body, supplies material which renews some structure or maintains some vital process; and it is distinguished from a medicine in that the latter modifies some vital action, but does not supply the material which sustains such action.

— Edward Smith (physician)

The same nutritive elements exist in both vegetable and animal foods, and … within certain limits, the two classes of food are interchangeable.

— Edward Smith (physician)

Every … element, whether mineral or organic, which is required for nutrition is found in the vegetable kingdom.

— Edward Smith (physician)