The effectiveness of prophylactic desensitizing nutrition of workers at microbiological industry enterprises has been evaluated. Three groups of workers were under study. Two groups of subjects were in contact with microbiological synthesis products: one group (prophylactic) was given a specially developed prophylactic ration; the second one (control) received usual nutrition, the third group (intact) was composed of subjects who had no contact with the harmful production factors. Before the use of preventive measures, changes in the lipid and protein metabolism were recorded in workers of microbiological industry, and sensitization to microbiological synthesis products was observed enhancing the development of allergic diseases of the broncho-pulmonary apparatus and skin. The use of a specially developed ration has promoted metabolism normalization, the lowering of sensitization degree, and produced a favourable effect on the disease course. The prophylactic ration has been recommended for workers engaged in the microbiological industry.