Research of Dr Käkelä focuses on the roles of lipids and fatty acids in cellular functions, pathogenesis of human diseases, aquatic food webs, and environmental adaptation of animals. Basic research and applied projects are carried out. The main methods are mass spectrometry-based lipidomics and several chromatographic techniques. Käkelä is responsible for the study courses: BSc Seminar in Physiology and Neuroscience, Animal Ecophysiology, Physiological Ecotoxicology and Functional Lipidomics Seminar, and contributes to several other courses as well e.g. the course Membranes, Carbohydrates and Lipids. He is supervising several MSc and PhD students, and runs a core facility Helsinki University Lipidomics Unit. The resources of the Lipidomics Unit are used for undergraduate and postgraduate student training.