Though Bouchardat (1806-1886) read his first memoir to the Academy of Sciences in 1838, and the final edition of his book appeared in 1875, he came into prominence through important contributions in the decade 1840 to 1850. Like Rollo and all other founders of the dietetic treatment, he considered diabetes a disease of digestion. According to his theory, normal gastric juice has no action upon starch, which is digested in the intestine; but in diabetes, an abnormal ferment digests starch in the stomach, and glycosuria, polyuria, and other symptoms result. He claimed to demonstrate the presence of diastase in the vomitus of diabetics and its absence in that of normal persons. Hypertrophy of the stomach and atrophy of the pancreas in diabetic necropsies were also held to support his theory; and he was thus the first to suggest an influence of the pancreas in the causation of diabetes, and the originator of the attempt to produce it by pancreatectomy in dogs. For sugar determination in urine, he used fermentation, the polariscope, and the Frommherz copper reagent. By the fermentation method he showed the presence of sugar in diabetic blood, but found none in normal blood. At how low an ebb was the Rollo treatment at this time is shown by the pleading and arguments of Bouchardat. He begs all friends of truth to hear him; whatever be the original cause of glycosuria, diabetics, who otherwise all die, are actually saved when his dietetic treatment is used. 

Bouchardat in the clinical field ranks with Claude Bernard in the experimental field. He is easily the most brilliant clinician in the history of diabetes. He resurrected and transformed the Rollo treatment, and almost all the modern details in diabetic therapy date back to Bouchardat. He was first to insist on the need of individualizing the treatment for each patient. He disapproved the rancid character of the fats in the Rollo diet, but followed an intelligent principle of substituting fat and alcohol for carbohydrate in the diet. He forbade milk because of its carbohydrate content. He urged that patients eat as little as possible, and masticate carefully; also (1841) he inaugurated the use of occasional fast-days to control glycosuria. Subsequently he noted the disappearance of glycosuria in some of his patients during the privations of the siege of Paris. 

Though the introduction of green vegetables is credited by Prout to Dr. B. H. Babington, the honor of thus successfully breaking the monotony of the Rollo diet, properly belongs to Bouchardat. He recommended them as furnishing little sugar, a little protein and fat, but especially potassium, organic acids, and various salts. He also devised the practice of boiling vegetables and throwing away the water, to reduce the quantity of starch when necessary. As a similar trick he "torrefied" (i.e., charred and caramelized) bread to improve its assimilation; possibly this is the origin of the widespread medical superstition that diabetics may have toast when other bread must be forbidden. He invented gluten bread; this started the idea of bread substitutes, from which sprang the bran bread of Prout and Camplin, Pavy's almond bread, Seegen's aleuronat bread, and the numerous later products. 

Bouchardat also first introduced the intelligent use of exercise in the treatment of diabetes, and reported the first clinical experiments proving its value. He showed that carbohydrate tolerance is raised by outdoor exercise; and to a patient requesting bread, he replied: "You shall earn your bread by the sweat of your brow." 

There is a modern sound to his complaints of the difficulties of having treatment efficiently carried out in hospitals, of the lack of adequate variety of suitable foods, of deception by patients, and of how, even when improved in hospital, they break diet and relapse after returning home. He advocated daily testing of the urine, to keep track of the tolerance and to guard against a return of sugar without the patient's knowledge. 

He followed Mialhe in giving alkalies, viz. sodium bicarbonate up to 12 to IS gm. per day, also chalk, magnesia, citrates, tartrates, soaps, etc., also ammonium and potassium salts; he found them often beneficial to the patients but not curative of the glycosuria. He told a patient: "You have no organic disease; there is merely a functional weakness of certain parts of your apparatus of nutrition. Restore physiological harmony and you will attain perfect health." 

He used glycerol for sweetening purposes, and introduced both levulose and inulin as forms of carbohydrate assimilable by diabetics, for reasons which well illustrate his intellectual keenness. On giving cane sugar to diabetics, he had found only glucose excreted. Was the levulose utilized or changed into glucose? Levulose proved under certain conditions to be more easily destroyed in vitro than glucose. Accordingly he gave levulose and inulin to diabetics, and found no sugar in the urine. Therefore he recommended levulose for sweetening purposes, and inulin-rich vegetables for the diabetic diet.

Main Works:

• Manuel de matière médicale de thérapeutique et de pharmacie, (1838, fifth edition 1873) – Materia medica manual of therapeutics and pharmacy.

• Eléments de matière médicale et de pharmacie (Paris 1839) – Elements of materia medica and pharmacy.

• Nouveau formulaire magistral, etc. (1840, 19th edition 1874).

• De la glycosurie ou Diabète sucré son traitement hygiénique, Paris, (1875, second edition 1883) – On glycosuria or diabetes mellitus and its hygienic treatment.

• Traité d'hygiène publique et privée basée sur l'etiology, 1881 – Treatise on public and private hygiene, based on etiology.[2]