Increased costs associated with greater adherence to the EAT-Lancet Commission reference diet in the province of Québec: the PREDISE Study

Abstract

The diet proposed by the EAT-Lancet Commission has faced criticism concerning its affordability. This study aimed to investigate the cost associated with a greater alignment to the EAT-Lancet reference diet in the province of Québec, Canada. The dietary habits of 1147 French-speaking adults were assessed using repeated web-based 24-h recall data collected between 2015 and 2017 in the cross-sectional PRÉDicteurs Individuels, Sociaux et Environnementaux (PREDISE) study. Diet costs were calculated using a Nielsen food price database. Usual dietary intakes and diet costs were estimated using the National Cancer Institute’s multivariate Markov Chain Monte Carlo method. Adherence to the EAT-Lancet diet was assessed using the EAT-Lancet dietary index (EAT-I). Associations between diet costs and EAT-I scores were evaluated using linear regression models with restricted cubic splines. After adjustment for energy intake, a higher EAT-I score (75th v. 25th percentiles) was associated with a 1·0 $CAD increase in daily diet costs (95 % CI, 0·7, 1·3). This increase in diet costs was mostly driven by the following component scores of the EAT-I (75th v. 25th percentiles, higher scores reflecting greater adherence): vegetables (1·6 $CAD/d, 95 % CI: 1·2, 2·1), free sugars (1·6 $CAD/d, 95 % CI: 1·3, 1·9), fish and plant-based proteins (1·4 $CAD/d, 95 % CI: 1·0, 1·8), fruits (0·9 $CAD/d, 95 % CI: 0·4, 1·3) and whole grains (0·4 $CAD/d, 95 % CI: 0·0, 0·8). Inversely, a greater score for the poultry and eggs component was associated with reduced diet costs (–1·2 $CAD/d, 95 % CI: −1·7, −0·7). This study suggests that adhering to the EAT-Lancet diet may be associated with an increase in diet costs in the province of Québec.