In the older times these persons were said to have been nourished by angels or devils; but according to Hammond many cases both of diabolical abstinence from food and of holy fasting exhibited manifest signs of hysteric symptoms.
Hammond, in his exhaustive treatise on the subject of "Fasting Girls," also remarks that some of the chronicles detail the exact symptoms of hysteria and without hesitation ascribe them to a devilish agency.

For instance, he speaks of a young girl in the valley of Calepino who had all her limbs twisted and contracted and had a sensation in her esophagus as if a ball was sometimes rising in her throat or falling into the stomach--a rather lay description of the characteristic hysteric "lump in the throat," a frequent sign of nervous abstinence.
Abstinence, or rather anorexia, is naturally associated with numerous diseases, particularly of the febrile type; but in all of these the patient is maintained by the use of nutrient enemata or by other means, and the abstinence is never complete.
A peculiar type of anorexia is that striking and remarkable digestive disturbance of hysteria which Sir William Gull has called anorexia nervosa.

In this malady there is such annihilation of the appetite that in some cases it seems impossible ever to eat again.

Out of it grows an antagonism to food which results at last, and in its worst forms, in spasm on the approach of food, and this in its turn gives rise to some of those remarkable cases of survival for long periods without food.
As this goes on there may be an extreme degree of muscular restlessness, so that the patients wander about until exhausted.
According to Osler, who reports a fatal case in a girl who, at her death, only weighed 49 pounds, nothing more pitiable is to be seen in medical practice than an advanced case of this malady.

The emaciation and exhaustion are extreme, and the patient is as miserable as one with carcinoma of the esophagus, food either not being taken at all or only upon urgent compulsion.
Gull mentions a girl of fourteen, of healthy, plump appearance, who in the beginning of February, 1887, without apparent cause evinced a great repugnance to food and soon afterward declined to take anything but a half cup of tea or coffee.