Eicosanoids (or icosanoids) are hormones made of lipids. They are signaling molecules made by the oxidation of 20-carbon fatty acids.
They have control over many bodily systems. They influence growth during and after physical activity, inflammation or immunity after the intake of toxic compounds and pathogens. They are also messengers in the central nervous system.
The networks of controls that depend upon eicosanoids are among the most complex in the human body.