NIACIN 451 



B. Forms of Occurrence 543 



C. Sites of Occurrence 544 



D. Stability in Food 545 



E. Influence of Soil, Environment, and Heredity 546 



F. Nicotinic Acid in U. S. Diets 547 



G. Antivitamins in Food 548 



H. Occurrence in Various Tissues 550 



X. Effects of Deficiency 550 



A. In Microorganisms 550 



B. In Man and Animals 551 



1. Relation of Biochemical Functions of Nicotinic Acid to Deficiency 

 States 551 



2. The Deficiency State 552 



3. Nicotinic Acid and Coenzyme Tissue Levels 554 



4. Urinarj' Excretion of Nicotinic Acid and Other Substances . . 556 



5. Stomach 560 



6. Heart 561 



7. Brain 561 



8. Skin 562 



9. Eyes 563 



10. Blood 563 



11. Miscellaneous 564 



XI. Pathology 565 



A. In Animals 565 



1. Dogs 565 



2. Hogs. . 567 



3. Rats 568 



4. Cotton Rats and Mice 569 



5. Rabbits 569 



6. Chicks, Turkeys, and Ducks 569 



7. Other Species 570 



B. In Man 570 



XII. Pharmacology 571 



A. Toxicity 571 



1. Rats and Mice 571 



2. Dogs 572 



3. Other Species 572 



B. Toxicity in Diets 573 



C. Circulation 573 



D. Blood Sugar 574 



E. Ketosis 575 



F. Gastric Secretion 575 



G. Serum Bilirubin 576 



H. Antiallergic Effects 576 



I. Other Effects 577 



XIII. Requirements and Factors Influencing 578 



A. Animals 578 



B. Man 586 



