BILE-ACIDS AND PH VALUES IN TOTAL FECES AND IN FECAL WATER FROM HABITUALLY OMNIVOROUS AND VEGETARIAN SUBJECTS

Twenty habitually omnivorous subjects and 19 habitually lactoovovegeta rian subjects aged 59-65 y collected feces during 4 consecutive days. The concentrations of bile acids in total feces did not differ between the omnivores and vegetarians, but the bile acid concentrations in fe cal water were significantly lower in the vegetarians. The concentrati on of the colorectal cancer-predicting bile acid deoxycholic acid in f ecal water was explained by the intake of saturated fat and the daily fecal wet weight (r2 = 0.50). Fecal pH did not differ between the omni vores and vegetarians. This variable was significantly (P < 0.05) expl ained by the intake of calcium (r2 = 0.30); 24-h fecal wet weight and defecation frequency were significantly higher in the vegetarians. In conclusion, out vegetarian subjects had a lower concentration of deoxy cholic acid in fecal water, higher fecal wet weight, and higher defeca tion frequency than the omnivorous subjects.