Spirulina

Studies in people

• Open question

  Algae as nutritious food³

  Spirulina is a protein-rich food with vitamins and fats, and studies show people accept it well.

• Benefit

  Muscle damage from exercise⁴

  In people, spirulina may prevent muscle damage from exercise, but how it works is unclear.

• Benefit

  Brain health in children⁵

  In malnourished children, spirulina seemed to help motor, language and thinking skills, but scientists do not yet know enough.

• Benefit

  Exercise recovery and fitness⁶

  Spirulina may help untrained and moderately trained people recover faster from exercise and improve aerobic fitness.

• Benefit

  Multiple sclerosis symptoms⁷

  In people with MS, spirulina lowered two inflammation markers and improved energy, movement and sexual function.

• Benefit

  Weight and blood fats⁸

  In people, spirulina supplements helped lower body weight, waist size and blood fats.

• Benefit

  Heart and blood sugar health⁹

  In people, spirulina supplements lowered weight, cholesterol, blood sugar and inflammation, but studies were small and mixed.

• Benefit

  Metabolic syndrome risk¹⁰

  Human studies suggest spirulina may help prevent or treat problems related to metabolic syndrome.

• Benefit

  Anemia in older adults¹²

  In older people, spirulina supplements raised red blood cell measures and white blood cell counts over 12 weeks.

• Benefit

  Arm exercise performance¹⁴

  In men, taking spirulina for a week raised hemoglobin and lowered heart rate and oxygen use during arm cycling.

• Benefit

  Muscle soreness after hard exercise¹⁶

  In elite male rugby players, spirulina prevented rises in some markers of muscle damage and inflammation after exhaustive exercise.

Animal and lab studies only

• Benefit

  Brain and nerve health²⁴

  In lab studies, spirulina showed anti-inflammatory and antioxidant effects in the brain.

• Benefit

  Pancreatic cancer growth²⁵

  In lab and animal studies, spirulina and its pigments slowed the growth of pancreatic cancer cells.

• Benefit

  Liver protection²⁶

  In animal studies, biscuits with spirulina powder reduced signs of liver injury caused by a harmful chemical.

• Benefit

  Gut bacteria in bread²⁷

  In lab studies, gluten-free bread with spirulina had more prebiotic activity than the same bread without it.

Study type not stated

• Benefit

  Immune and antioxidant effects¹⁸

  Spirulina is a blue-green algae rich in vitamins and pigments that may support the immune system and fight inflammation.

• Benefit

  Nutritional value and health uses¹⁹

  Spirulina is packed with protein, vitamins and minerals, and studies suggest it may help with diabetes, cancer and heart conditions.

• Benefit

  Gut bacteria and overall health²³

  Spirulina is an edible microbe rich in vitamins and minerals, and eating it appears to promote the growth of gut bacteria.

Found in some samples or products

These come from where it was grown, how it was processed or cooked, or what it was made into. They are not about the ingredient itself, so the signal does not count them.

• Plastic bits in food supplements²⁰

  Packaged spirulina was found to contain tiny plastic bits, mostly fibers, in most brands tested.

How it’s made and used

• Bread texture and taste¹¹

  Adding spirulina to bread made it firmer and greener, and tasters liked it less at higher amounts.

• Pasta taste and texture¹³

  Adding spirulina to pasta changed how firm and sticky it was, but tasters still liked it overall.

• Pasta nutrition and taste¹⁵

  Adding spirulina to pasta raised its protein and fiber, but tasters liked plain pasta best.

• Muscle recovery after exercise¹⁷

  In people, taking spirulina for 15 days did not ease soreness or speed muscle recovery after hard arm exercise.

• Protein from algae²¹

  Spirulina is one of the richest protein sources among microbes, with levels similar to meat and soybeans.

• Protein nutrition²²

  Spirulina is 55–70% protein and contains all the essential amino acids your body needs.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.