Data comprise of radionuclide and stable element concentrations in vegetal and animal food and feedstuffs, and their corresponding transfer coefficients and concentration ratios determined in Mediterranean ecosystems in Spain. The considered foodstuff groups are: cereals, grapevine (including wine), olive tree (including olive oil), lamb, beef, pork, and dairy products from sheep, goat and cow. The data include: elemental and radioactive concentration in soil, plants, food and feedstuffs; dry to fresh ratios for foodstuffs; animal feeding diet; estimation of overall elemental and radioactive diet concentration; transfer coefficients for vegetal foodstuffs (relating dry matter elemental and radionuclide concentration in foodstuff to the dry matter concentration in soil); and concentration ratios for animal foodstuffs (relating fresh matter elemental and radionuclide concentration in foodstuff to the dry matter concentration in feedstuff). Radionuclide concentrations presented include Ra-226, Cs-137, Ra-228 and K-40. Elemental concentrations presented include Cs, Sr, K, Na, Ca, Mg, P, Pb, U and Th. Full details about this dataset can be found at https://doi.org/10.5285/48d5395e-e9fb-45ed-b69f-1ea0d2d36be6