Calimore wrote:From a classic text by Edward Alsworth Ross. "Suggestibility". Chapter 2 in Social Psychology: An outline and source book. New York: Macmillan Co. (1919): 11 - 4
Fasting heightens suggestibility
Fasting heightens susceptibility to hallucination and suggestion. The universally recommended regimen for hearing voices, experiencing ecstatic states, and "seeing God" is fasting. There was an ancient saying, "The stuffed prophet shall not see or know secret things." The Indian boy about the time of puberty fasts till he is vouch safed a vision of his "Manitou." In the earlier days the negro, "seekers" fasted in order to experience "conversion." Savage peoples employ fasting, solitude, and physical exhaustion induced by watching, dancing, whirling, shouting, or flagellation, to bring on abnormal states in which suggestibility is extreme. The preternatural resonance of the half-starved human being has long been counted a sign of divine afflatus, and the full-fed healthy man of stable mentality has humbled himself before the emaciated seer of visions and dreamer of dreams.
http://www.brocku.ca/MeadProject/Ross/Ross_1919/Ross_1919_02.html
I'm not sure how much one should trust anything so old that they still refer to anyone as "savage peoples" let alone "negroes." We have come a long long way in psychology since then, the stance of fasting could be very different.
I remember I found a book once that was from that era and it had a chapter about how "Negroes engage in unusual sexual behavior because they know that they are not white enough to engage in normal sexual behavior" and kept referring to anal sex as "negro-style." In that same book, it claimed that homosexuality is the result of an Oedipus Complex that is realized as wrong, so then the child blocks themselves from being attracted to not just their mother, but all women, and then channels their sexual energy into men to fill the gap.
So. . . Psychology from the 1910s is probably not very reliable is what I'm saying.