Spinach and beef can be eaten together. These two foods have no conflict or mutual interaction, are not toxic, and will not produce toxic substances. The oxalic acid and calcium salts contained in spinach can combine to form calcium oxalate crystals, so spinach cannot be eaten with foods high in calcium such as tofu, milk, and beef mainly contains high-quality protein. Not only can spinach and beef be eaten together, but they can also achieve food complementary effects.