This section is from the book "Practical Dietetics With Special Reference To Diet In Disease", by William Gilman Thompson. Also available from Amazon: Practical Dietetics with Special Reference to Diet in Disease.
Melons are of little service for nutrition, but they are so agreeable to the palate that they are in very general use. The varieties commonly obtainable in this country are the cantaloupe, or muskmelon, and watermelon, and of these, the former is less likely to produce gastro-intestinal disorder when not eaten too freely.
These fruits contain so large a proportion of water - upward of 95 per cent - that they are not satisfying to the appetite; and since in hot weather they are cool and refreshing, overindulgence in them is a common fault, and most of the ill repute of watermelons has arisen in this way rather than from any specific injurious effect which they produce. If eaten with other food, they dilute the gastric juice. Well-ripened muskmelons may often be eaten by invalids in moderation to promote the appetite, served at the commencement of a meal, at which time it is best that most fruit should be eaten when taken with other food. Citrons are very indigestible.