Shift from a Mixed Diet to a Lactovegetarian Diet: Influence on Some Cancer-Associated Intestinal Bacterial Enzyme Activities

This investigation studied the effects of a shift from a mixed diet to a lactovegetarian diet on some cancer-associated bacterial enzymes in human feces (β-glucuronidase, β-glucosidase, and sulphatase). Three months after the shift to the lactovegetarian diet, there was a significant decrease in β-glucuronidase, β-glucosidase, and sulphatase activities per gram feces wet weight (p <0.05, <0.05, and <0.001, respectively). In contrast, glucuronide and glucoside hydrolysis remained unchanged per gram dry weight, although sulphatase activity was still significantly lowered when expressed this way (p < 0.01). However, the fecal excretion increased significantly (p < 0.05). Part of the explanation for the decreased enzyme activities is obviously a dilution effect, because much of the increased fecal weight after the shift in diet was associated with a higher water content. The higher water content was probably due to a higher fiber intake (p < 0.001). Thus, the results in this paper indicate that a change from a mixed diet to a lactovegetarian diet leads to a decrease in certain enzyme activities proposed to be risk factors for colon cancer.