Voegtlin (17) has recently described experiments in the treatment of pellagra, which seem to fall little if any short of a demonstration that pellagra is a deficiency disease in the same sense as beri-beri or scurvy. This investigator has been one of the most careful students of the etiology of the disease. In 1914 (18) he made the first attempt to interpret the nature of the deficiencies of the diets which are common among those classes of people of the United States among whom pellagra is of frequent occurrence. He proposed (1) a deficiency or absence of certain "vitamins"; (2) the presence of some toxic substances; (3) a deficiency in certain amino-acids. Later researches, especially those of McCollum and Simmonds have shown that the articles which entered into the diet used by Goldberger, cannot contain sufficient amounts of toxic substances to account for the ill-effects observed when animals are restricted to them singly or collectively. Concerning the other two proposed explanations for pellagra, both are still debatable contributing factors.

In 1914 Voegtlin tested on over one hundred patients in the pellagra hospital at Spartanburg, the effects of two types of diets on the clinical condition of the disease (18). Patients with a moderate attack of pellagra uncomplicated by any other disease, were placed upon a diet which closely resembled that which they were accustomed to before the attack. These will be designated as diets X and Y. Diet X consisted of the following ingredients :

Wheat bread ..... 300 grams.

Butter ........ 30 "

Cabbage ....... 100 "

Corn meal (maize) ___ 50 "

Ham ......... 25 "

Hominy ........ 75 "

Corn syrup ...... 75 "

Pork ......... 50 "

Potatoes ........ 150 "

Prunes ........ 30 "

Turnip tops ...... 100 "

Sugar ......... 40 "

Milk ......... 40 "

This diet contained 50.5 grams of protein; 89.8 grams of fat; 350.8 grams of carbohydrate, and yielded 2473 calories of energy.

Of the effect of restricting pellagra patients to this diet Voegt-lin says: "Almost without exception the general clinical condition of these patients remained either stationary or gradually became more aggravated simultaneously with an increase in the pellagrous manifestations. The skin lesions often spread to parts of the body which had not been affected previously; there was also an increase in the stomatitis and the gastro-intestinal symptoms. The appetite, as a rule, was good for the first few weeks, but diminished gradually. The nervous manifestations, such as disturbances in sensation, reflexes, and mentality either showed no change or increased in severity. A few cases developed an acute psychosis. A careful examination of the dietary record showed that the patients had consumed sufficient food." The patients were changed after a time to diet Y, the composition of which was given as follows:

Wheat bread ...... 300 grams.

Butter ......... 45 "

Corn meal ...... 50 "

Eggs ......... 100 "

Meat ........ 100 "

Orange juice ..... 100 "

Potatoes ....... 150 "

Prunes ........ 30 "

Sugar ......... 40 "

Milk ......... 1000 "

This diet contained 102.9 grams of protein; 115.3 grams of fat; 316.2 grams of carbohydrates, and furnished 2781 calories of energy.

On diet Y, which differed from diet X in containing 4 eggs, 100 grams of fresh beef and one liter of milk (somewhat more than one quart), the patients showed gradual improvement, ending in many cases in the complete disappearance of all recognizable manifestations of the disease. Another group of patients which was placed on diet Y immediately upon their admission to the hospital, showed definite improvement within two weeks. Within two months the patients were judged to have recovered from the disease, except in a relatively few cases in which it was far advanced. Some of these did not show any benefit from the improved dietary.

Voegtlin next placed patients on diet X for a time until it was observed that their clinical condition remained stationary or grew gradually worse. Some were then given one of the following extracts of natural food-stuffs:

(1) A fat-free, alcoholic extract of yeast or rice polishings.

(2) A fat-free alcoholic extract of ox liver or thymus gland.

The first of these extracts was chosen because it contained a great abundance of the anti-beri-beri substance, water-soluble B. The second contained a relative abundance of fat-soluble A and water-soluble B. The results indicated that the administration of extracts of yeast or rice polishings did not modify the course of the disease in patients maintained on diet X, with the possible exception of one case in which certain well-marked nervous symptoms disappeared coincident with the treatment. Voegtlin states that "the administration of the liver preparation to pellagrins was followed by an improvement in their condition, apparently comparable to that produced by the consumption of a diet containing a considerable amount of milk, eggs and meat. The evidence so far available, therefore, indicates that the dietary defect presumably responsible for pellagra is distinctly different from, and probably more complex than the one causing human beri-beri."

If these results are confirmed by further experiments it is difficult to see any other interpretation which can be placed upon them than that pellagra is a specific deficiency disease, due to the lack of some substance or substances which are not abundant in the articles which entered into the composition of diet X, but were more abundant in milk, eggs and meat, at least in liver. Voegtlin does not imply that pellagra is necessarily due to a deficiency of the diet in a specific substance such as a hypothetical pellagra "vitamin," proposed by Funk. He holds rather that the pellagrous syndrome is caused by a combination of the deficiencies in some of the well-recognized food factors.