Microalgae are the renewable green gold of future generations, capturing sunlight and producing oxygen and biomass through photosynthesis. Its biomass consists of valuable compounds with applications in the food industry as well as in the cosmetics, nutraceutical and pharmaceutical and biofuel industries. Polyunsaturated fatty acids (PUFAs) production through microalgae depends on the species and is affected by culture conditions such as nutrients, salinity, light intensity periods, temperature, pH and even association with other microorganisms. Omega-3 fatty acids are primarily synthesized from algae and phytoplankton and transferred to fish and marine mammals via the food chain. The defensive effect of omega-3 fatty acids towards cardiovascular diseases development most probably relates to the beneficial modification of a wide range of risk factors, including blood pressure, plasma triacylglycerol concentrations and inflammation.