Ecological stoichiometry (ES) is an ecological theory used to study the imbalances of chemical elements, ratios, and flux rates among organisms and the environment to better understand nutrient cycling, energy flow, and the role of organisms in ecosystems. Parasitologists can use this framework to study phenomena across biological scales from genomes to ecosystems. By using the common currency of elemental ratios such as carbon:nitrogen:phosphorus, parasitologists are beginning to explicitly link parasite-host interactions to ecosystem dynamics. Thus, ecological stoichiometry provides a framework for studying the feedbacks of parasites on the environment as well as the effects of the environment on parasites and disease.