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.
Personal idiosyncrasy is a very potent factor in dyspepsia. Not only do individuals vary from one another in this regard, but the same person varies at different periods, in different stages of health, or at different ages. One not uncommonly observes persons who are most confirmed dyspeptics at home, but who when at sea are able to eat and digest all manner of richly cooked and thoroughly indigestible food without either nausea or discomfort, only to return to their dyspepsia on shore. On the other hand, many persons whose digestion is normal at home are made constipated and dyspeptic by the lack of exercise and by other conditions at sea, even though they be never "seasick." How often do dyspeptics who have been long kept upon a rigid regimen break away from all restraint and give astonishing accounts of the forbidden articles which they have suddenly discovered they can eat for a time with impunity! One who cannot digest the most tender mouthful of prepared meat or a crust of dry bread will thrive upon enormous quantities of nuts and oranges; another requires a preposterous quantity of pickles or of Cayenne pepper to stimulate the sluggish digestion into any sort of activity, and another lives largely upon raw apples!
Many people cannot eat strawberries without attacks of heartburn, dyspepsia, and angina, while for others they are very wholesome food. Some persons cannot eat cauliflower without exciting dyspepsia, and for others the use of melted butter invariably brings on such an attack, while butter spread upon bread does not. Others exhibit intolerance for twice-cooked meats, new bread, potatoes, sweet jams of any kind, etc. (See Idiosyncrasies in Regard to Food, P-397).
Fats and greasy foods set up butyric-acid fermentation which causes heartburn, regurgitation, and a rancid disagreeable taste.
Sweets and raw or insufficiently cooked starches cause lactic-acid and other fermentations, with flatulence.
Dyspepsia is often caused by the continued abuse of irritants, such as alcohol and highly seasoned food, pickles, mustard, Cayenne.
To enumerate all the various substances which may at some time or other cause indigestion would be to include practically the entire list of foods. Each new case must be separately studied, and general rules admit of many exceptions.
Balfour concisely sums up the relations of food to enfeebled stomach digestion by saying: "Three things greatly disturb gastric comfort - too large a meal, too short an interval between the meals, and, lastly, the ingestion of food into a stomach still digesting".
It is important at the outset to understand all the patient's habits of daily life, the amount of sleep and exercise taken, the hours of meals and quantity and quality of food eaten, habits of drinking or smoking, the habit of the bowels, condition of the stools, and the nature of any irregularity - the habit of eating too fast or taking too much or too little fluid with the meals. The condition of the teeth and tongue and breath must also be observed, and in obscure cases the possible existence of sources of reflex irritation, like ovarian disease, must be investigated. The proper cooking of the food should be insisted upon. Thorough cross-examination in regard to all of these conditions may reveal habits not suspected by the patient to be injurious, and which may be easily corrected.