Background: The aim of this study was to investigate the psychometric properties of Social Capital Questionnaire ( SCQ) developed by Onyx and Bullen (2000) among a sample of medical science students in Tehran University of Medical Sciences, Iran and to compare the factor analysis with findings from two previous studies in Australia and the United States.

Background: There is evidence of an inverse association between yoghurt intake and risk of colorectal cancer (CRC). We aimed at investigating the association between the intake of yoghurt and other dairy foods consumed in Iran and CRC risk. Methods: Our analysis included 4070 subjects within the IROPICAN (Iran Study of Opium and Cancer) study. Detailed information was collected by the use of validated questionnaires. We estimated adjusted odds ratios (OR) and 95% confidence intervals (CI) for the association between the intake of total dairy products, and, separately, of yoghurt, milk, cheese, kashk, dough, cream, ice cream, and other milk products, and CRC using unconditional logistic regression analyses. The intake was categorized in tertiles. Results: Overall, we analyzed 865 cases and 3205 controls. Total dairy products intake was not associated with CRC. The OR for one tertile increase (OR_T) in yoghurt intake was 0.97 (95% CI 0.87–1.08) for CRC and 0.66 (95% CI 0.52–0.84) for proximal colon cancer. Cream intake was associated with CRC (OR_T3 = 1.33, 95% CI 1.08–1.64), colon (OR_T3 = 1.37, 95% CI 1.03–1.81), and proximal cancer (OR_T3 = 1.29, 95% CI 1.04–1.61). The OR of distal colon cancer for ice cream intake was 0.59 (95% CI 0.43–0.82). Other dairy products were not associated with CRC risk.

As colorectal cancer (CRC) is largely due to modifiable lifestyle habits, the awareness on its risk factors is highly important. Dietary fatty acids have been linked to CRC risk. We explored the association between dietary trans fatty acids (TFAs) intake and CRC risk. We analyzed 865 CRC cases (434 in colon and 404 in rectum) and 3206 controls of the IROPICAN study, with data collected by trained interviewers using validated questionnaires. TFAs intake (industrial and ruminant types) was categorized into quartiles. Multivariate logistic regression models were built to calculate the odds ratios (OR) for the association between CRC and TFAs. We observed a positive association between industrial TFAs and colon cancer (OR for highest vs lowest quartile [OR_Q4vsQ1] = 1.28, 95% confidence interval 1.07–1.54). A higher association was observed between industrial TFAs and CRC, occurring after 50 years of age. In addition, elaidic acid was associated with an increased risk of colon (OR_Q4vsQ1 = 1.58, 1.24–2.02) and specifically of proximal colon cancer (OR _Q4vsQ1 = 2.12, 1.40–3.20), as well as of rectum cancer (OR_Q4vsQ1 = 1.40, 1.07–1.83). An inverse association was observed between ruminant TFAs intake and colon cancer risk (OR_Q4vsQ1 = 0.80, 0.67–0.97). Industrial TFAs, such as semisolid/solid hydrogenated oils, may increase the risk of CRC, especially colon and proximal colon cancer. In contrast, ruminant TFAs do not appear to be associated with CRC. Awareness programs and regulatory actions regarding hydrogenated oils are warranted, given their high consumption through ultra-processed foods in more developed and less developed countries.