As sub-Saharan Africa undergoes rapid nutritional transition, the intersection of environmental sustainability and chronic disease prevention has never been more consequential. Most dietary research frames sustainability and health as parallel goals — this longitudinal work from Ghana tests whether they can be measured together as a single, culturally grounded index and whether that index actually predicts who develops obesity, diabetes, or hypertension over time.
Drawing on the RODAM-Pros cohort — 1,499 Ghanaian adults aged 20 to 82, followed for approximately seven years — researchers constructed an Optimized Diet Index (ODI) scored from 0 to 90. The index was built from Ghana-specific food propensity data and simultaneously weighted for nutritional adequacy, cultural acceptability, a 50% reduction in greenhouse gas emissions, and affordability. The median ODI score was only 29 out of a possible 90, indicating substantial room for improvement across the cohort. Higher ODI adherence was associated with rural Ghanaian residence, older age, lower total energy intake, and, notably, lower educational attainment — a pattern that inverts the typical socioeconomic gradient seen in Western diet-quality research. Associations between ODI scores and incident general and abdominal obesity, type 2 diabetes, and hypertension were assessed per 10-point increment via multivariable-adjusted logistic regression.
The study's multi-criteria index design is methodologically notable and represents an advance over single-dimension sustainability scores common in European and North American literature. However, several caveats deserve attention. Dietary data were collected only at baseline using a food propensity questionnaire, which captures habitual patterns but may miss within-person variation over a seven-year follow-up. The cohort's dual-site structure — comparing Ghanaians at home versus migrants in Amsterdam — introduces meaningful heterogeneity in food environments that complicates direct cross-group inference. With a sample under 1,500, subgroup analyses by sex and site will be underpowered. This is confirmatory groundwork rather than definitive causal evidence, but it meaningfully extends the sustainability-health conversation into an under-represented African population context.
