N-nitroso compounds (NOCs) are a class of chemical carcinogens found in various environmental sources such as food, drinking water, cigarette smoke, the work environment, and the indoor air population. We conducted a systematic review and meta-analysis to investigate the links between nitrate, nitrite, and NOCs in food and water and the risk of gastrointestinal (GI) cancers, including esophageal cancer (EC), gastric cancer (GC), colorectal cancer (CRC), and pancreatic cancer (PC). A systematic search of the literature in Scopus, PubMed, Google Scholar, Web of Science, ScienceDirect, and Embase was performed for studies on the association between NOCs in drinking water and food sources and GI cancers. Forest plots of relative risk (RR) were constructed for all the cancer sites and the intake sources. The random-effects model was used to assess the heterogeneity between studies. Forty articles were included after removing duplicate and irrelevant articles. The meta-analysis indicated that the intake of high dose vs. low dose of these compounds was significantly associated with the overall GI cancer risk and nitrite (RR = 1.18, 95% CI = 1.07–1.29), and N-nitrosodimethylamine (NDMA) (RR = 1.32, 95% CI = 1.06–1.65). We found that dietary nitrite intake increased GC (RR = 1.33, 95% CI = 1.02–1.73), and EC (RR = 1.38, 95% CI = 1.01–1.89). Additionally, dietary NDMA intake increased the risk of CRC (RR = 1.36, 95% CI = 1.18–1.58). This meta-analysis provides some evidence that the intake of dietary and water nitrate, nitrite, and NOCs may be associated with GI cancers. In particular, dietary nitrite is linked to GC and EC risks and dietary NDMA intake is associated with CRC.

The relationship between diet, including its inflammatory potential, and breast cancer has led to inconsistent results. We investigated the association between a dietary inflammatory index (DII) an...

Background: Total antioxidant capacity (TAC) indicates the quality of individuals’ diet. It has been proposed as a valuable measure for evaluating the potential protective effects of dietary antioxidants. The aim of this study is to assess the relationship between the dietary TAC and odds of non-alcoholic fatty liver disease (NAFLD) in Yazd, Iran. Methods: This case-control study included 115 patients diagnosed with non-alcoholic fatty liver disease (NAFLD) and 102 age- and sex-matched controls without NAFLD, all recruited from the same medical clinic. After 12 h of fasting, serum concentration of liver enzymes, fasting blood glucose and lipid profile of case and control groups were measured. To evaluate the participants’ dietary intake during the past year a semi-quantitative Food Frequency Questionnaire which was validated for Iranian population, were used. Results: There was no significant association between TAC and the risk of NAFLD in the whole population. However, risk of NAFLD in men those in top tertile of vegetable oil TAC were higher than men in the lowest tertile in crude model (OR = 3.81, CI: 1.19–12.2; P = 0.01). This relationship was attenuated and no longer statistically significant after adjusting for confounding variables. Conclusions: In the current study, no significant association was observed between NAFLD and dietary TAC, although in men who had a higher intake of vegetable oil TAC, a higher risk of NAFLD was observed. Further well-designed prospective studies are warranted to clarify these relationships.

Previous studies have mainly focused on individual food groups and nutrients in relation to breast cancer and few studies have considered diet as a whole variable. The aim of this study was to examine the association of dietary diversity score (DDS) and alternative healthy eating index-2010 (AHEI-2010) with odds of breast cancer. In this case-control study, we enrolled 477 pathologically confirmed cases of breast cancer and 506 age-matched controls. Dietary assessment was done using a food frequency questionnaire. Dietary indices including DDS and AHEI-2010 were constructed according to standard methods. After controlling for potential confounders, we found a significant inverse association between DDS and odds of breast cancer; individuals in the highest tertile of DDS had 37% lower odds for having breast cancer compared with those in the lowest tertile (OR: 0.63, 95% CI: 0.42–0.95). Such a significant inverse association was also seen among post-menopausal women; such that after taking potential confounders into account, women in the top tertile of DDS score were 60% less likely to have breast cancer compared with those in the bottom tertile (OR: 0.40, 95% CI: 0.19–0.83). With regard to AHEI, we found no significant association between AHEI score and odds of breast cancer either before or after controlling for potential confounders. This association remained non-significant either in pre-menopausal or post-menopausal women. We found that adherence to a diet with high diversity was associated with decreased odds of breast cancer. However, no significant association was observed between AHEI and breast cancer.