“…According to previous studies in the West, not only various factors including age (Everhart et al, 1989;Sandler et al, 1990;Campbell et al, 1993;Dukas et al, 2003), sex (Everhart et al, 1989;Sandler et al, 1990;Campbell et al, 1993), smoking status (Dukas et al, 2003), alcohol consumption (Dukas et al, 2003;Sanjoaquin et al, 2004), body mass index (BMI) (Sandler et al, 1990;Dukas et al, 2003;Sanjoaquin et al, 2004), and physical activity (Everhart et al, 1989;Sandler et al, 1990;Dukas et al, 2003;Sanjoaquin et al, 2004), but also several aspects of diet such as intakes of energy (Sandler et al, 1990;Towers et al, 1994), dietary fiber (Dukas et al, 2003;Sanjoaquin et al, 2004), and nonalcoholic beverages (Sandler et al, 1990;Sanjoaquin et al, 2004) have been associated with constipation. However, information on this issue is quite limited among people in Asian countries including Japan (Kunimoto et al, 1998;Wong et al, 1999;Nakaji et al, 2002;Fujiwara, 2003), where dietary habits and foods available differ considerably from those in Western countries.…”