Dietary Resistant Starch Contained Foods and Breast Cancer Risk: a Case-Control Study in Northwest of Iran

Background: A protective effect of resistant starch (RS) containing foods on carcinogenesis has been shownfrom several lines of experimental evidence for gastrointestinal cancers. Therefore, we aimed to investigatethe association between RS contained foods and breast cancer (BC) risk in a hospital-based, age- and originmatched,case-control study. Materials and
Methods: A validated, semi-quantitative, food frequency questionnaire(FFQ) was completed by 306 women newly diagnosed with BC aged 25 to 65 years, and 309 healthy women asmatched controls. Odds ratios (ORs) and 95% confidence intervals (95%CI) were estimated using conditionallogistic regression models.
Results: Reduced BC risk was associated with the highest tertile of whole-wheatbread and boiled potato consumption with adjusted ORs at 0.34 (95%CI: 0.19-0.59) and 0.61 (95%CI: 0.37-0.99), respectively. Among consumers of whole-wheat bread consumers were considered, the protective role ofcereals remained relatively apparent at higher intakes level of fiber rich breads at adjusted models (OR=0.53,95%CI: 0.28-1.01). Moreover, high intake of legumes was found out to be a significant protective dietary factoragainst risk of BC development with an OR of 0.01 (95%CI: 0.03-0.13). However, consumption of white breadand biscuits was positively related to BC risk.
Conclusions: Our results show that certain RS containing foods,in particular whole wheat bread, legumes and boiled potato may reduce BC risk, whereas higher intake of whitebread and biscuits may be related to increased BC risk.