What’s the difference between chlorella and spirulina?

    Last Updated: October 13, 2024

    Chlorella is a single-cell green alga that lives in freshwater, while spirulina, despite its common name of “blue-green algae”, is a genus of cyanobacteria that forms filamentous, multicellular colonies in saltwater. The nutrient profiles of chlorella and spirulina are quite similar — both contain carbohydrates, protein, folate, riboflavin, thiamine, iron, and polyunsaturated fatty acids, though chlorella contains more omega-3 fatty acids while spirulina is higher in omega-6 fatty acids. Spirulina also contains copper, which is absent from chlorella. Chlorella has higher levels of vitamin A, iron, magnesium, niacinamide, and phosphorus compared to spirulina.[1][2] Finally, while chlorella supplements are a good source of vitamin B12, the B12 in spirulina supplements is often biologically-inactive pseudovitamin B12.[3]

    One key difference between these two microalgae is the way they’re produced: as a cyanobacterium, spirulina lacks a cellulose cell wall, and once it’s harvested and dried, it’s ready for consumption. This characteristic also improves spirulina’s bioavailability.[4] On the other hand, chlorella in its natural form does contain a cellulose cell wall, which must be broken down mechanically to make chlorella fit for human consumption.[5]