At 113-ha in size and dating to the 3rd millennium cal BC, the ditched enclosure site of Marroquíes is one of the latest mega-sites in Iberia. The settlement preserves multiple mortuary areas which contain over 450 individuals, allowing for the examination of inter-individual and inter-group variability in diet and health. This study presents the first large-scale palaeodietary assessment of the site through the analysis of carbon (δ13C) and nitrogen (δ15N) stable isotope values from 113 human and 23 faunal samples. It also offers the first comprehensive analysis of dental disease at Marroquíes in a sample of over 4,600 human teeth. Humans at Marroquíes exhibit mean values of 8.4 ± 0.9‰ for δ15N and -19.3 ± 0.3‰ for δ13C, suggesting a diet predominantly based on proteins from terrestrial C3 plant foodwebs, conforming to a broader dietary pattern common throughout Late Prehistoric Iberia. Dental analyses revealed significant differences in the frequency of hypoplasias and calculus between mortuary areas. Overall, the documented variability within mortuary areas is higher than variability between them, suggesting that although differences in consumption patterns did exist, the bonds created by group affinities outweighed the expression of social asymmetries at death