Sitting on cold surfaces does not cause hemorrhoids. According to a study done in 2009:
Out of 38 possible aetiological factors 20 showed no significant bivariate correlation to TEH: gender, nationality, professions like employee, worker, housewife, and self-employed, the assumption to have haemorrhoids, previous anal surgery , diarrhoea [24-26], laxative use , hard bowels [24,26], straining at defaecation [10,24,25,27], sitting on cold surfaces , lifting a heavy load [24-28], coughing, sneezing [24,27], spicy meals [27,28], use of shower or wet wipes after defaecation , pregnancy [6,27,28], and current menses . Since these variables were not significant, they were no longer traced throughout the remainder of the analyses.
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The remaining 16 factors showed a significant bivariate relationship to TEH: age, careers as trainee, civil servant or retirement, participant in anoreceptive sex , engagement in excessive physical effort , engagement in sports [27,28], recent alcohol intake [27,28], frequency of bathtub use [23,30], frequency of shower use [23,31], frequency of genital cleaning before sleep [23,31], use of dry toilet paper after defaecation combined with wet cleaning [23,31], use of gels/soaps after defaecation [23,31], use of dry toilet paper only [23,31], and pregnancy [6,27,28].