Clinical Nutrition

Carbohydrate quantity and quality affect the risk of endometrial cancer: A systematic review and dose-response meta-analysis

Data on the association of dietary intake of total carbohydrates as well as dietary glycemic index (GI) and glycemic load (GL) with risk of endometrial cancer are contradictory. Therefore, we conducted a systematic review and dose-response meta-analysis of observational studies to summarize available findings in this field. The online databases were searched for relevant publications to May 2018 using relevant keywords. Overall, eight prospective cohort and five case-control studies with a total sample size of 734,765 individuals, aged ≥18 years, and 8466 cases of endometrial cancer were included. Although the overall association between dietary intake of total carbohydrates and risk of endometrial cancer was non-significant, we found a significant positive association in some subgroups of cohort studies including those with ≥10 years' duration of follow-up (combined effect size: 1.29, 95% CI: 1.09-1.53, P = 0.003) and studies with sample size of ≥50,000 participants (combined effect size: 1.24, 95% CI: 1.08-1.43, P = 0.002). In addition, a non-linear dose-response relationship was found in this regard after considering the estimates from cohort studies (P Although the overall associations of dietary total carbohydrate intake, GI, and GL with risk of endometrial cancer were not significant, there were significant positive associations in some subgroups of the included studies, particularly those with high quality. There was also a dose-response association between dietary total carbohydrate intake, GI and GL, and risk of endometrial cancer.

Association of plasma branched-chain amino acid with multiple cancers: A mendelian randomization analysis

Diet and ovarian cancer risk: An umbrella review of systematic reviews and meta-analyses of cohort studies

Diet may play an important role in the etiology of ovarian cancer (OC). We aimed to evaluate the strength and credibility of evidence pertaining to dietary risk factors for OC. We comprehensively searched PubMed, Web of Science, Cochrane, CINAHL, JBI Database of Systematic Reviews and Implementation Reports, PROSPERO and EMBASE databases to identify related systematic reviews and meta-analyses of prospective cohort studies. This study had been registered at PROSPERO. The registration number is CRD42020187651. For each association, we estimated the summary effect size using fixed and random effects models, the 95% confidence interval and the 95% prediction interval. We assessed heterogeneity, evidence of small-study effects, and excess significance bias. A total of 22 systematic reviews and meta-analyses were included in the present study. These previous reports evaluated 184 individual studies, which proposed a total of 36 associations between dietary factors and OC risk. Out of the 36 associations, there were no strong, highly suggestive and suggestive evidence, only four (black tea, skim/low-fat milk, lactose, and calcium) were determined to be supported by weak evidence. OC risk was inversely associated with intake of black tea or calcium, and positively associated with intake of skim/low-fat milk or lactose. Our studies revealed that four associations between OC risk and dietary factors (black tea, skim/low-fat milk, lactose, and calcium) were supported by weak evidence. The remaining 32 associations were not confirmed. Additional studies are needed to carefully evaluate the relationship between dietary factors and OC risk.

Association between pre-diagnostic dietary pattern and survival of ovarian cancer: Evidence from a prospective cohort study

Evidence for a role of single nutrition or foods on ovarian cancer (OC) survival has been limited and inconclusive. Due to the potentially complex interactions in dietary, we applied dietary patterns to this study to firstly explore the relationship between the pre-diagnosis overall diet and OC survival. The prospective cohort study was conducted among 853 OC patients aged 18-79 years during 2015-2020. Dietary intake was collected using a validated 111-item food frequency questionnaire. Deaths were obtained by medical records and cancer registry up to March 31, 2021. Cox proportional hazards regression models was used to evaluate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of pre-diagnosis dietary patterns with overall survival (OS). Overall, during the follow-up period (median: 37.57 months, interquartile: 25.00-50.17 months), 130 (18.49%) OC patients died. Four dietary patterns were identified: healthy pattern, ethnic pattern, animal foods pattern, and sweet pattern. The highest tertile of the healthy pattern scores was related to better OS compared with the lowest tertile scores (HR = 0.54, 95% CI = 0.30-0.98, p trend <0.05), whereas OC patients with highest adherence to the animal foods pattern was associated with worse OS than those with the lowest adherence (HR = 1.90, 95% CI = 1.14-3.17, p trend <0.05). We found no significant associations between adherence to ethnic pattern and sweet pattern and OS of OC patients. Pre-diagnosis healthy patterns was associated with better OC survival, whereas animal pattern was associated with worse survival among OC survivals.

Fat intake modifies association between cigarette smoking and lung cancer in a prospective cohort study: A potential explanation for the lung cancer paradox

Association between intake of the n-3 polyunsaturated fatty acid docosahexaenoic acid (n-3 PUFA DHA) and reduced risk of ovarian cancer: A systematic Mendelian Randomization study

Whether the intake of docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid, is beneficial for ovarian cancer (OC) remains controversial and we hope to disentangle this puzzle using genetic data from large-scale populations in European and Asian. We employed, for the first time, a systematic Mendelian randomization (MR) design to comprehensively evaluate the causal effect of plasma DHA levels, an objective biomarker of DHA intake, on OC risk in European and then verified the extrapolation of the results in the Asian. Data in the analysis included genetic association data obtained from large-scale genome-wide association studies with 13,499 individuals for plasma DHA measurements and 66,450 individuals for OC in the European population, and 1361 individuals for plasma DHA measurements and 61,457 individuals for OC in the Asian population. The causal relationship between DHA and OC was estimated using the inverse-variance weighted approach, together with extensive validation and sensitivity analyses to verify the main results. In the European population, MR evidence suggested a causal relationship between higher plasma DHA levels and lower OC risk (OR, 0.89 for OC per one-SD increment in DHA; 95% CI, 0.83 to 0.96; P = 0.003). Subgroup analysis by histological type of OC indicated that this observed association was stronger among endometrioid ovarian cancer (EOC) (OR, 0.82; 95% CI, 0.69 to 0.96; P = 0.014). A similar causal association of borderline significance was reached in the Asian replication set. The above results were consistently supported by a series of validation and sensitivity analyses. Our study provided robust genetic evidence for a protective association between plasma DHA levels and lower risk of OC, especially EOC, in the European population. These findings may inform prevention strategies and interventions directed towards DHA intake and OC.

Nut and peanut butter intake are not directly associated with the risk of endometrial or ovarian cancer: Results from a Dutch prospective cohort study

Nut intake has been associated with reduced cancer-related mortality and cancer risk. However, very few studies investigated the association between nut consumption and the risk of endometrial and ovarian cancer, with inconclusive results. We prospectively examined the relation between total nut, tree nut, peanut, and peanut butter intake and the risk of endometrial and ovarian cancer in the prospective Netherlands Cohort Study (NLCS). In 1986, 62,573 women aged 55-69 years were included in the NLCS. At baseline, all participants filled in a questionnaire and a subcohort of 2589 women was randomly selected. After 20.3 years of follow-up, 389 endometrial and 347 ovarian cancer cases with complete data were included in the analysis. Hazard ratios (HRs) were calculated in multivariable-adjusted Cox regression analyses, using a case-cohort approach. Compared to nonconsumers, the HRs (95% confidence intervals) for women consuming 10 + g total nuts/day were 1.23 (0.82-1.87) for endometrial cancer and 0.84 (0.57-1.24) for ovarian cancer. For tree nut, peanut, and peanut butter intake, also no significant relations with endometrial or ovarian cancer were observed. In the endometrial cancer analyses, significant interactions of total nut intake with body mass index and cigarette smoking status were found. The results of this study suggest that intake of total nuts, tree nuts, peanuts, and peanut butter is not related to the risk of endometrial or ovarian cancer. The observed interactions in the endometrial cancer analyses, in particular with cigarette smoking status, require confirmation in other studies.