Higher dietary total antioxidant capacity is not associated with risk of breast cancer in Iranian women

The association between dietary total antioxidant capacity and odds and severity of irritable bowel syndrome among Iranian adults: a cross-sectional study

Background

Little evidence is available in terms of the role of dietary antioxidants in the management of irritable bowel syndrome (IBS) disease. This study aimed to examine the association between dietary total antioxidant capacity (dTAC) and odds of IBS and its severity.

Methods

This cross-sectional study was conducted on 3,362 Iranian adults who were referred to health centers in Isfahan province, Iran. Participants' dietary intakes were collected using a semi-quantitative validated food frequency questionnaire (DS-FFQ). The dTAC was measured by the ferric-reducing antioxidant power (FRAP) method. Multivariable binary or ordinal logistic regression analyses were performed to estimate any associations between dTAC and odds of IBS, IBS severity, and IBS subtypes.

Results

The average age and BMI of the participants and dTAC score were 36.3 ± 7.87 year, 24.9 ± 3.82 kg/m2. The prevalence of IBS, IBS with constipation (IBS-C), IBS with diarrhoea (IBS-D), mixed IBS (IBS-M), and un-subtyped IBS (IBS-U) were 22.2, 7.5, 4.6, 3.8, and 6.2%, respectively. In crude and adjusted models, the results did not show any significant association between dTAC and odds of IBS among whole and gender-age stratified populations. Being in the third compared with the first tertile of dTAC was not also significantly associated with odds of IBS severity. Besides, there were no significant associations between dTAC and odds of IBS-C, IBS-D, IBS-M, and IBS-U.

Conclusion

This study indicates that dTAC may not be associated with the odds of IBS and its severity even after stratification for gender and body mass index.

Dietary Total Antioxidant Capacity and Odds of Breast Cancer: A Case-Control Study

Breast cancer (BC) is the most frequently diagnosed female cancer worldwide. It has been shown that oxidative stress can contribute to cancer development. Therefore, we investigated the association between dietary total antioxidant capacity (TAC) and breast cancer risk in a case-control study. This study was conducted on 136 newly diagnosed breast cancer patients and 272 hospitalized controls in Tehran, Iran. Participant habitual diet was obtained using a 168-item validated food frequency questionnaire. Dietary TAC scores were computed using two different methods: the dietary ferric reducing antioxidant potential (FRAP) method and oxygen radical scavenging capacity (ORAC). The association between dietary TAC and breast cancer risk was estimated by logistic regression. The score of DTAC calculated by ORAC method was associated with lower odds of BC, especially among premenopausal women. However, this association was not significant after controlling potential confounders (ORAC: OR Q4-Q1 = 1.01, 95% CI = 0.42-2.44, p-trend = 0.96). Estimation of DTAC by FRAP method was not associated with the risk of BC (FRAP: OR Q4-Q1 = 1.04, 95% CI = 0.53-2.05, p-trend = 0.8). There were no association detected based on menopausal status. In this study, dietary TAC was not significantly related to the odds of breast cancer.

Interaction between Apo A-II -265T > C polymorphism and dietary total antioxidant capacity on some oxidative stress and inflammatory markers in patients with type 2 diabetes mellitus

This work aims to examine the interaction between apo A2 (Apo A-II) -265T > C SNP and dietary total antioxidant capacity (DTAC) on inflammation and oxidative stress in patients with type 2 diabetes mellitus. The present cross-sectional study included 180 patients (35-65 years) with identified Apo A-II genotype. Dietary intakes were assessed by a FFQ. DTAC was computed using the international databases. IL-18 (IL18), high-sensitivity C-reactive protein (hs-CRP), pentraxin (PTX3), serum total antioxidant capacity (TAC), superoxide dismutase (SOD) activity and 8-isoprostaneF2α (PGF2α) markers were obtained according to standard protocols. General linear model was used to evaluate the interaction. The interaction of gene and DTAC (P_FRAP = 0·039 and P_ORAC = 0·042) on PGF2α level was significant after adjusting for confounders. A significant interaction was observed on IL18 level (P_ORAC = 0·018 and P_FRAP = 0·048) and SOD (P_TEAC = 0·037) in obese patients. Among patients whose DTAC was higher than the median intake, the levels of hs-CRP and PGF2α were significantly higher only in individuals with CC genotype. Serum TAC (P_FRAP = 0·030, P_ORAC = 0·049) and SOD were significantly lower in the CC genotype. There was a favourable relationship between the high-DTAC and SOD (obese: P_TEAC = 0·034, non-obese: P_FRAP = 0·001, P_TRAP < 0·0001, P_TEAC = 0·003 and P_ORAC = 0·001) and PGF2α (non-obese: P_ORAC = 0·024) in T-allele carriers. The rs5082 SNP interacts with DTAC to influence several cardiometabolic risk factors. Also, we found dietary recommendations for antioxidant-rich foods intake might be useful in the prevention of diabetes complications in the T carrier more effectively than the CC genotype. Future large studies are required to confirm these results.

Association of Dietary Total Antioxidant Capacity with Cancer Recurrence and Mortality among Breast Cancer Survivors: A Prospective Cohort Study

Antioxidants decrease the risk of breast cancer by reducing oxidative stress, but the association between dietary total antioxidant capacity (DTAC) and cancer recurrence has not yet been investigated. The present study aimed to test the hypothesis that DTAC is inversely associated with cancer recurrence and mortality in breast cancer patients. Breast cancer patients (n = 603) who underwent breast cancer surgery and a dietary survey within 5 years after surgery were recruited. This study observed disease-free survival (DFS) and mortality in breast cancer patients according to DTAC calculated based on 24-hr dietary recall. Total DTAC was significantly lower in patients with cancer recurrence than in those without. DFS was positively associated with the total DTAC (p = 0.005) and DTAC of vegetables and legumes (p = 0.001 and p = 0.010), respectively. However, total DTAC was not associated with mortality. Cox proportional hazards regression analysis showed that total DTAC (HR: 0.44, 95% CI 0.26-0.94) and DTAC of vegetables (HR: 0.30, 95% CI 0.14-0.65) and legumes (HR: 0.38, 95% CI 0.18-0.73) were inversely associated with cancer recurrence after adjusting for confounding factors. This study was the first to indicate that total DTAC and DTAC of vegetables and legumes could be beneficial in decreasing breast cancer recurrence.

Higher Fruits and Vegetables Consumption Is not Associated with Risk of Breast Cancer in Iranian Women

We aimed to investigate the association of fruits and vegetables (FVs) and their all subgroups intakes with breast cancer (BC) risk in Iranian women.

The present case-control study conducted on 150 age-matched women with newly diagnosed BC and apparently healthy controls. Anthropometric measures were collected and eventually, the mean intakes of total FVs and each subgroup were obtained from a validated 147-item food frequency questionnaire. Multivariate regression analysis was used to estimate odds ratios (OR) with 95% confidence intervals (CI).

Our findings revealed that the intake of only dark yellow vegetable was significantly higher in BC patients (P = 0.03) after controlling for covariates. OR of BC across tertiles of FVs intake, showed that there was not any statistical association of total FVs (OR: 1.83, CI: 0.54-6.24, P-trend = 0.3) and their subgroups intakes with BC risk. Except for berry fruits intake which was adversely associated with BC risk (OR: 0.36, CI: 0.09-1.37, P-trend = 0.02).

Our findings did not support the hypothesis that higher total FVs and their subgroups intakes reduce BC risk and suggested that only higher berry fruits intake may have an association with lower BC risk.