Chronic bronchitis, which is usually accompanied by emphysema, is commonly a late sequel of cardiac or renal disease, and under these circumstances the dietetic treatment is that appropriate to the primary affection. Many cases, however, occur in which marked chronic bronchitis exists, for a time at any rate, without any serious disturbance of the cardiac and renal systems. Such cases have developed as a result of exposure to unfavourable climatic conditions in susceptible subjects, or as the result of the immoderate use of alcohol. Sooner or later, however, in all cases, cardiac weakness supervenes, and in turn aggravates the bronchial condition.

The essential point underlying the dietetic treatment of all cases of chronic bronchitis is to keep in mind that there is always an associated limitation of the digestive powers, the amount of this being in proportion to the severity of the bronchial affection. The existence of chronic bronchitis always implies a certain degree of chronic disturbance of the circulation in the mucous membrane of the digestive tract, with associated disturbance of the digestive secretions, and limitation in the digestive power. The appreciation of the fact is the keynote to the successful dietetic treatment of chronic bronchitis.

The diet must be light and nutritious, many "extras" must be cut off, the pleasures of the table must, to some extent, be denied. Carbohydrate foods must be specially restricted, on account of their tendency to induce flatulent dyspepsia. The necessity of restricting the carbohydrates is all the greater in obese subjects; such cases indeed may sometimes be advantageously treated for their obesity. The principal meal of the day should be taken in the middle of the day rather than at night, and there should be a restriction in the amount of liquid taken with meals. In the chronic bronchitis of old people the meals should be small and frequently administered, and of such a nature as is little liable to cause flatulence. In these cases a little alcohol (2 ounces daily) is often advantageous. Dietaries appropriate to this condition are given in detail on pp. 404 et scq.