en Nutrition Nutrition Original Research: Clinical Science Original Research: Clinical Science <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><b><span style="font-size:9.0pt"><span style="font-style:normal">Background: </span></span></b><span style="font-size:9.0pt"><span style="font-style:normal">Rectal cancer (RC) is one of the most commonly occurring cancers in Iran in recent years. Dietary intakes of Omega-3 (&omega;-3), Omega-6 (&omega;-6), and fiber have been thought to diminish the risk of RC. Therefore, this study was conducted to evaluate the association of dietary &omega;-3, &omega;-6, and fiber with the risk of RC.</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Methods:</b> In this case-control study, dietary intakes of &omega;-3 and &omega;-6 were estimated using a 148-item food frequency questionnaire (FFQ) between 363 people (162 cases, 201 control) aged 20&ndash;80 years old.&nbsp; Cases were patients with RC, and controls were healthy people. Odds ratios (OR) and 95% confidence intervals (CI) were assessed using logistic regression models.</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Results:</b> According to the multiple logistic regression model with the backward method, dietary fiber intake was inversely associated with RC as a protective factor (OR=0.3; 95%CI= 0.1-0.9; </span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal">=0.038).&nbsp; Also, it was observed that dietary &omega;-3 had an inverse borderline association with RC (OR= 0.5; 95%CI= 0.3-1.02; P=0.060), after adjusting for other studied variables. However, the association of &omega;-6 with RC was not statistically significant (OR=1.1; 95%CI= 0.7-1.8; </span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal">=0.730).</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span style="font-family:&quot;Times New Roman&quot;,serif"><span style="font-style:italic"><b><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; Conclusion:</span></span></b><span style="font-size:9.0pt"><span style="font-style:normal"> Although no association between &omega;-3 and &omega;-6 intake was observed with the risk of RC, adequate daily intake of dietary fiber may protect us against RC risk.</span></span></span></span></span></span></span></span><br> &nbsp; Fiber, ω -3, ω -6, Rectal cancer 850 856 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-4796-2&slc_lang=en&sid=1 Payam Hosseinzadeh payam.gildrc@gmail.com 200319475328460092596 0009-0009-5628-4640 No Gastrointestinal and Liver Diseases Research Center (GILDRC), Iran University of Medical Sciences (IUMS), Tehran, Iran Ali Gholami gholamia1@nums.ac.ir 200319475328460092597 200319475328460092597 No Noncommunicable Diseases Research Center, Neyshabur University of Medical Sciences, Neyshabur, Iran Mahdi Alemrajabi alemrajabi@miums.ac.ir 200319475328460092598 200319475328460092598 No Firoozgar Hospital, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Hasan Ghodsi ghodsih1979@gmail.com 200319475328460092599 200319475328460092599 No Healthy Ageing Research Centre, Neyshabur University of Medical Sciences, Neyshabur, Iran Yasamin Mohammadzade mohammadzadehy1@nums.ac.ir 200319475328460092600 200319475328460092600 No Khayyerin-e-salamat Hospital, Qom University of Medical Sciences, Qom, Iran Bahareh Amirkalali amirkalalib1@nums.ac.ir 200319475328460092601 200319475328460092601 No Gastrointestinal and Liver Diseases Research Center (GILDRC), Iran University of Medical Sciences (IUMS), Tehran, Iran Farhad Zamani payam.gildrc@gmail.com 200319475328460092602 200319475328460092602 Yes Gastrointestinal and Liver Diseases Research Center (GILDRC), Iran University of Medical Sciences (IUMS), Tehran, Iran