B3 -
B3 Deficiency of nicotinic acid (niacin - vitamin B3) in diet causing skin eruptions, nervous disorders and gastrointestinal disturbances. Webster's dictionary 1979
Chchoke, Dr Anthonyh J The Complete Book of Enzyme Therapy foreword by Dr Hoffer, Abram cites the hypothesis of  Rudin, Dr D who contends that pellagra is due to a prostaglandin deficiency,  Prostaglandins are made from essential fatty acids.  Pellagra may occur due to a deficiency of (a) essential fatty acids (omega 3 and/or omega 6 oils) or a deficiency of (b) minerals and/or vitamins (especially B3 and/or B6) needed for enzymes to make needed transformations.  The 2nd type Rudin calls "substrate pellagra" when the "substrate essential fatty acids" are lacking.  Enzymes need such cofactors and substrates to optimize body utilization of food.
Kummerow, Fred A - - "In our (Andrew Saul) October 2014 column, I had the honor and privilege of interviewing Professor Fred A. Kummerow, Ph.D., near his 100th birthday. You may remember 2-part interview entitled 'From Pellagra to Trans Fats and Beyond. How a Legendary Nutritional Scientist Is Still Saving Countless Thousands From Premature Deaths.' (1). 
Dr. Kummerow’s life-saving nutritional efforts began with helping to wipe out the deadly pellagra epidemic in the United States. Thanks to researchers including Drs. Kummerow, Joseph Goldberger and Conrad Elvehjem, pellagra is essentially non-existent today in the U.S. Pellagra is a disease that was present before 1938 in the southeastern United States. It is a deficiency of niacin (vitamin B3). The symptoms of pellagra are swelling of the lips and tongue and swelling of the arms to the point that the skin breaks open. When it reaches this stage, the people usually die. 
When Professor Kummerow arrived at Clemson, SC, in 1943, thousands of people were still dying of pellagra. Some 3,000–6,000 people were dying each year (about 5 per 100,000 population). He figured out how to put niacin in corn grits, a food staple
in the south. By 1945, there were only 12 deaths from pellagra and it is rare today.
It’s now more than 70 years later and pellagra is extremely rare, so that’s roughly 250,000 lives he saved from premature death."
The major psychoses and neuroses as omega-3 essential fatty acid deficiency syndrome: substrate pellagra. 
Biol Psychiatry. 1981 Sep;16(9):837-50. Rudin DO. Pellagra was once a major cause of 3 behaviorally different mental disorders-schizophreniform, manic-depressive-like, and phobic neurotic + drying dermatoses, autonomic neuropathies, tinnitus, and fatigue.
In this preliminary study all three of the corresponding present-day mental diseases
are found to exhibit, statistically, the same pellagraform physical disorders but to ameliorate not so much with vitamins as with supplements of a newly discovered trace omega-3 essential fatty acid (w3-EFA), which provides the substrate upon which niacin and other B vitamin holoenzymes act uniquely to form the prostaglandin 3 series tissue hormones regulating neurocircuits en block. Since present-day refining and food selection patterns, as well as pure corn diets, deplete both the B vitamins and W3-EFA, the existence of therapeutically cross-reacting homologous catalyst and substrate deficiency forms of pellagra are postulated, the 1st contributing to the B vitamin deficiency epidemics of 50-100 years ago, the second to the more recent endemic "Diseases of Western Civilization" which express in certain genetic subgroups as the major mental illnesses of today.
Rudin, DO (1982) 
The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome." Medical Hypotheses
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would constitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modernized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by out diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w30EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.