Why didn't people believe dr. goldberger's conclusion about the cause of pellagra? give two reasons?

In claiming that pellagra was a nutritional disorder rather than an infectious disease, Dr. Goldberger went against established medical tradition.

Furthermore, pellagra was prevalent in orphanages in the southern United States, and southerners were irate to think that the diet they were feeding their wards was deficient. But a diet of gruel made from corn meal didn't cut the mustard.