Background: The associations between 1-carbon metabolism (OCM) nutrients (methionine, folate, vitamin B-6, and vitamin B-12) and Alzheimer disease (AD) remains inconclusive. Objectives: This study aimed to investigate the association of dietary OCM nutrients with subsequent risk of AD and further assess whether participants with high genetic risk for AD might benefit from dietary OCM nutrients. Methods: We analyzed data from 192,214 participants who completed at least one 24-h dietary questionnaire and had no previous history of AD based on the UK Biobank. Nutrients intake was calculated using McCance and Widdowson's The Composition of Food and USDA's Food and Nutrient Database for Dietary Studies. Cox proportional models with restricted cubic splines were applied to explore the associations. Results: Over a median follow-up of 13.35 y, 959 cases of AD (41 early-onset cases and 918 late-onset cases) were identified. Compared with those in the low-intake OCM group (quartile 1), participants in the high-intake OCM group (quartile 4) had reduced risk of developing AD. The corresponding hazard ratios (HRs) and 95% confidence intervals (CIs) for methionine, folate, vitamin B-6, and vitamin B-12 intake were 0.66 (0.54, 0.80), 0.71 (0.58, 0.87), 0.71 (0.59, 0.87), and 0.77 (0.64, 0.93), respectively. Similar associations were observed in late-onset AD. In early-onset AD, high methionine and vitamin B-12 intake were associated with 70% (HR: 0.30; 95% CI: 0.10, 0.86) and 71% (HR: 0.29; 95% CI: 0.09, 0.96) reduction in risk, respectively. Participants with low genetic risk and high OCM nutrients intake had >75% reduced AD risk compared with high-risk, low-intake participants. Conclusions: In this prospective cohort study, we found that higher intake of OCM nutrients is associated with reduced risk of AD. Participants with high genetic risk of AD are more likely to benefit from dietary OCM nutrients intake.

ObjectiveThe association between Metabolic Syndrome (MetS), its components, and the risk of osteoarthritis (OA) has been a topic of conflicting evidence in different studies. The aim of this present study is to investigate the association between MetS, its components, and the risk of OA using data from the UK Biobank.MethodsA prospective cohort study was conducted in the UK Biobank to assess the risk of osteoarthritis (OA) related to MetS. MetS was defined according to the criteria set by the International Diabetes Federation (IDF). Additionally, lifestyle factors, medications, and the inflammatory marker C-reactive protein (CRP) were included in the model. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI). The cumulative risk of OA was analyzed using Kaplan-Meier curves and log-rank tests. To explore potential nonlinear associations between MetS components and OA risk, a restricted cubic splines (RCS) model was employed. In addition, the polygenic risk score (PRS) of OA was calculated to characterize individual genetic risk.ResultsA total of 45,581 cases of OA were identified among 370,311 participants, with a median follow-up time of 12.48 years. The study found that individuals with MetS had a 15% higher risk of developing OA (HR = 1.15, 95%CI:1.12-1.19). Additionally, central obesity was associated with a 58% increased risk of OA (HR = 1.58, 95%CI:1.5-1.66), while hyperglycemia was linked to a 13% higher risk (HR = 1.13, 95%CI:1.1-1.15). Dyslipidemia, specifically in triglycerides (HR = 1.07, 95%CI:1.05-1.09) and high-density lipoprotein (HR = 1.05, 95%CI:1.02-1.07), was also found to be slightly associated with OA risk. When stratified by PRS, those in the high PRS group had a significantly higher risk of OA compared to those with a low PRS, whereas no interaction was found between MetS and PRS on OA risks. Furthermore, the presence of MetS significantly increased the risk of OA by up to 35% in individuals with elevated CRP levels (HR = 1.35, 95% CI:1.3-1.4).ConclusionMetS and its components have been found to be associated with an increased risk of OA, particularly in individuals with elevated levels of CRP. These findings highlight the significance of managing MetS as a preventive and intervention measure for OA.

Background: Recent studies have shown that bile acids are essential in irritable bowel syndrome (IBS) pathology, and cholecystectomy has direct effects on bile acid metabolism. However, whether cholecystectomy increases the risk of IBS remains unclear. We aimed to investigate the association between cholecystectomy and IBS risk in the UK Biobank (UKB). Methods: This study is a prospective analysis of 413,472 participants who were free of IBS, inflammatory bowel disease, cancer, or common benign digestive tract diseases. We identified incidents of IBS through self-reporting or links to primary healthcare and hospitalization data. We evaluated hazard ratios (HRs) adjusted for sociodemographic characteristics, health behaviours, comorbidities, and medications. Results: During a median follow-up period of 12.7 years, we observed 15,503 new cases of IBS. Participants with a history of cholecystectomy had a 46% higher risk of IBS than those without (HR = 1.46, 95% CI: 1.32–1.60), and further subtype analysis showed that the risk of IBS with diarrhoea was significantly higher than the risk of IBS without diarrhoea (HR = 1.71, 95% CI: 1.30–2.25 vs. HR = 1.42, 95% CI: 1.28–1.58). The overall covariate-adjusted HRs for IBS were similar between the group with both cholecystectomy and gallstones (HR = 1.45, 95% CI: 1.32–1.58) and the group with cholecystectomy without gallstones (HR = 1.50, 95% CI: 1.36–1.67) when the group without both cholecystectomy and gallstones was used as a reference. The overall covariate-adjusted HR was not significantly different in the group without cholecystectomy with gallstones (HR = 1.18, 95% CI: 0.95–1.47). The positive association of cholecystectomy with IBS risk did not change when stratifying the data based on age, sex, BMI, smoking, alcohol consumption, healthy diet, quality sleep, physical activity, type 2 diabetes, hypertension, hyperlipidaemia, mental illness, NSAID intake, or acid inhibitor intake. Sensitivity analyses, including propensity score matching analysis and lagging the exposure for two or four years, indicated that the effects were robust. Conclusion: Cholecystectomy was associated with a higher risk of IBS, especially IBS with diarrhoea. Additional prospective randomized controlled and experimental studies are warranted to further validate the association and to explore the relevant biological mechanisms.