A clinical study was undertaken to evaluate the effectiveness of concentrated cabbage juice in the treatment of peptic ulcers. Patients at San Quentin Prison with a diagnosed ulcer crater were treated in a double blind control experiment. They were given either concentrated cabbage juice or placebo facsimile. The evaluation of the merit of this treatment was based upon repeated x-ray examinations of the ulcer crater. A period of 22 days was allowed for ulcer crater healing time. The results of this experiment indicated concentrated cabbage juice to be effective in healing of peptic ulcer.