Health and medical microalgae are microscopic, photosynthetic organisms that have gained increasing attention for their diverse health-promoting properties and potential therapeutic applications. Common species such as Spirulina, Chlorella, Dunaliella salina, and Haematococcus pluvialis are rich sources of bioactive compounds, including proteins, essential amino acids, vitamins, minerals, polyunsaturated fatty acids, pigments like chlorophyll and carotenoids, and antioxidants such as phycocyanin and astaxanthin.