Relationship between lifestyle factors and defecation in a Japanese population

There is a paucity of accurate data regarding any association in the general population between defecation and lifestyle factors such as diet, exercise, physique, and childbirth.

To evaluate the effects of such lifestyle factors on defecation among regional residents of Japan.

Residents (n = 1,699) of northern Japan, aged over 40 years, were surveyed in 1995 using a questionnaire to assess their lifestyle factors (diet, beverage consumption, exercise, physique, and childbirth), and examining their defecation status. We evaluated the relationship between these lifestyle factors and defecation using logistic regression analysis. The authors used four measures (defecation frequency, subjective defecation state, subjective fecal properties, and fecal consistency) and assigned the subjects to a group defined by their defecatory status: constipation, diarrhea, or normal, depending on the responses of the subjects to all four criteria.

The tendency for constipation correlated positively with age in males ( p = 0.130), although this trend was not observed in females ( p = 0.641). Of the dietary factors examined, only rice, which accounts for the largest proportion of daily dietary fiber intake in Japan, demonstrated a preventive effect on constipation in both sexes ( p = 0.050 in males and 0.003 in females). Walking was a preventive factor for constipation among males ( p = 0.049), and alcohol also inhibited constipation among males ( p = 0.007).

These results suggest that exercise, such as walking, and a high intake of dietary fiber, such as rice, were useful in the maintenance of defecation.