Consumption of Yoghurt and Other Dairy Products and Risk of Colorectal Cancer in Iran: The IROPICAN Study

Abstract

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.

Role of Dairy Foods, Fish, White Meat, and Eggs in the Prevention of Colorectal Cancer: A Systematic Review of Observational Studies in 2018–2022

“…However, in the other two cohort investigations [26,27] and one of the case-control researches [34] analysed in the present review, CRC did not show clear associations with the total dairy consumption. Moreover, in one case-control study [32], a direct association was found between total dairy intake and CRC risk.…”

“…Figure 1 shows the PRISMA flow diagram summarizing the identification and selection of the relevant publications. Twenty-one studies were included in the systematic review: fourteen cohort studies [18][19][20][21][22][23][24][25][26][27][28][29][30][31] and seven case-control studies [32][33][34][35][36][37][38].…”

“…Five cohort study [19][20][21]26,27] and three case-control study [32][33][34] comparisons were used to assess the association between the total dairy consumption and CRC risk. In three of the cohort studies [19][20][21], a significant inverse association was observed for CRC, in addition to CC and RC separately and, also, in subtypes according to tumour localisation (distal and proximal).…”

“…The analysis of the association of the total milk consumption with CRC risk included six cohort study [18,19,22,[24][25][26] and two case-control study [33,34] comparisons. No significant association was found in any of them, except for a weak inverse association with CC risk in one of the cohort studies [18] and a significant inverse association with the CRC risk in one of the case-control studies [33] and one of the cohort studies [25], this last association independent of sex and cancer sites [25,33].…”

Colon microbiota modulation by dairy-derived diet: new strategy for prevention and treatment of colorectal cancer

“…In this regard, the consumption of milk, cheese and yogurt revealed to be beneficial. [34][35][36] Considering this recent association between dairy products and the reduction of the risk of developing CRC, it is of our interest in this review to understand the mechanism through which this type of ingredients may protect the colon cells carcinogenesis.…”