Metabolomics Profiling of Dietary Patterns and Type 2 Diabetes Risk in a Nigerian Prospective Cohort: The Lagos Cardiometabolic Study

Metabolomics offers a molecular window into the biological mechanisms through which dietary patterns influence metabolic disease risk, yet no metabolomics-linked dietary study has been conducted in a Nigerian cohort. This study integrates untargeted plasma metabolomics profiling with prospective dietary data to identify metabolic signatures of dietary patterns predictive of incident type 2 diabetes mellitus among adults in Lagos State, South West Nigeria. A prospective cohort design enrolled 1,800 adults aged 35 to 65 years without prevalent diabetes at baseline, drawn from Eti-Osa, Surulere, and Lagos Mainland local government areas. Baseline dietary intake was assessed using a validated semi-quantitative food frequency questionnaire, and dietary patterns were derived by principal component and cluster analyses. Fasting plasma samples collected at baseline underwent high-resolution untargeted metabolomics profiling using liquid chromatography mass spectrometry. Participants were followed annually over four years for incident type 2 diabetes, defined by fasting glucose, glycated haemoglobin, or clinical diagnosis. Metabolome-wide association analyses examined associations between dietary pattern scores and metabolite concentrations. Cox proportional hazards regression modelled associations between metabolomics signatures and incident type 2 diabetes, adjusting for age, sex, body mass index, physical activity, and family history. Causal mediation analysis tested whether identified metabolites mediate the diet-diabetes relationship. Findings will generate the first dietary metabolomics data for sub-Saharan Africans, producing original evidence on biological pathways linking Nigerian dietary patterns to diabetes risk. Keywords: metabolomics, dietary patterns, type 2 diabetes, prospective cohort, Lagos.