Spirulina is a type of algae that grows in fresh or salt water. It comes as a supplement, in tablet or powder form. People use it for its health benefits, as it is rich in nutrients and has antioxidant properties.

Spirulina is among the world’s most popular supplements. It is made from an organism that grows in both fresh and saltwater.

It is a type of cyanobacteria, which is a family of single-celled microbes that are often referred to as blue-green algae. Just like plants, cyanobacteria can produce energy from sunlight via a process called photosynthesis.

Spirulina was consumed by the ancient Aztecs but became popular again when NASA proposed that it could be grown in space for use by astronauts.

These days, people use spirulina to boost the levels of nutrients and antioxidants in their bodies, and it may help protect against various diseases.

Here are 10 evidence-based health uses and benefits of spirulina.

Spirulina is packed with nutrients. A single tablespoon (tbsp), or 7 grams (g), of dried spirulina powder, contains:

  • Protein: 4 g
  • Thiamin: 14% of the Daily Value (DV)
  • Riboflavin: 20% of the DV
  • Niacin: 6% of the DV
  • Copper: 47% of the DV
  • Iron: 11% of the DV

It also contains small amounts of magnesium, potassium, and manganese.

In addition, the same amount contains only 20 calories and less than 2 g of carbohydrates.

Spirulina also provides a small amount of fat — around 1 g per tbsp (7 g) — including both omega-6 and omega-3 fatty acids in an approximately 1.5 to 1 ratio.

Plus, the quality of the protein in spirulina is considered excellent and provides all of the essential amino acids that your body needs.

Note that it is often claimed that spirulina contains vitamin B12, but this is false. It has pseudovitamin B12, which has not been shown to be effective in humans.


Spirulina is a type of blue-green algae that grows in both salt and fresh water. It is highly nutritious and a great source of protein, copper, and B vitamins.

The main component of spirulina is called phycocyanin, which is an antioxidant that also gives it its unique blue color.

Phycocyanin can help fight oxidative stress by blocking the production of molecules that promote inflammation and providing impressive antioxidant and anti-inflammatory effects.


Phycocyanin is the main active compound in spirulina. It has powerful antioxidant and anti-inflammatory properties.

Spirulina can help lower total cholesterol, low-density lipoprotein (LDL) or bad cholesterol, and triglycerides, while also increasing high-density lipoprotein (HDL) or good cholesterol, which are all risk factors for heart disease.

According to one review, spirulina was able to significantly improve these markers in people with metabolic syndrome and related disorders.


Studies indicate that spirulina can lower triglycerides and improve cholesterol levels, which may support heart health.

Fatty structures in your body are susceptible to oxidative damage. This is known as lipid peroxidation, a key driver of many serious diseases.

Research found that the antioxidants in spirulina may be particularly effective at reducing lipid peroxidation.

In fact, one small study showed that spirulina supplementation was able to reduce exercise-induced lipid peroxidation, inflammation, and muscle damage in 17 rugby players.


Fatty structures in your body can become oxidized, driving the progression of many diseases. Some research suggests that the antioxidants in spirulina may help prevent this.

5. May have anti-cancer properties

While more studies are needed, some evidence suggests that spirulina has anti-cancer properties.

Research in animals indicates that it may help reduce cancer occurrence and tumor size in various cancers.


Spirulina may have anti-cancer properties. However, more research is needed.

6. May reduce blood pressure

One review of five studies found that taking 1-8 g of spirulina per day could significantly reduce both systolic and diastolic blood pressure, especially for people with high blood pressure levels.

This reduction is thought to be driven by an increased production of nitric oxide, a signaling molecule that helps your blood vessels relax and dilate.


Spirulina may increase production of nitric oxide and reduce blood pressure levels, a major risk factor for many chronic conditions.

Spirulina is a popular alternative treatment for symptoms of allergic rhinitis, and there is evidence that it can be effective.

For instance, one study found that spirulina was more effective than cetirizine, an antihistamine used to treat allergies, in improving symptoms of allergic rhinitis and decreasing inflammation.

However, more research is needed.


Spirulina supplements may be effective against allergic rhinitis, but more research is needed.

8. Could be effective against anemia

Anemia is fairly common in older adults, leading to prolonged feelings of weakness and fatigue.

A 2020 study found that taking spirulina may improve anemia in pregnant people during the second trimester. In 2021, researchers also found it may also improve iron deficiency in young children.

However, more high-quality, recent studies are still needed.


Research suggests that spirulina may improve anemia in pregnant people, as well as iron deficiency in children.

9. May improve muscle strength and endurance

Exercise-induced oxidative damage is a major contributor to muscle fatigue.

Spirulina may help reduce this, as research points to improved muscle strength and endurance.

In another study, spirulina supplementation was able to improve oxygen uptake during an arm cycling exercise, with researchers noting that it could act as an ergogenic aid to enhance athletic performance.


Spirulina may provide multiple exercise benefits, including enhanced endurance and increased muscle strength.

10. Could support blood sugar control

Animal research suggests that spirulina could help lower blood sugar levels.

However, according to one review of eight studies on humans, spirulina supplementation in doses ranging from 0.8-8 g daily could significantly reduce fasting blood sugar levels in people with type 2 diabetes.

However, there was no significant effect on blood sugar levels after eating or levels of hemoglobin A1c, which is used to measure long-term blood sugar control.

Therefore, more research is needed.


Some evidence suggests that spirulina may benefit people with type 2 diabetes by significantly reducing fasting blood sugar levels. Still, more studies are needed.

What does spirulina do to the body?

Spirulina contains protein, vitamins, and minerals and has antioxidant properties. It may help manage inflammation, blood sugar, cholesterol, and blood pressure, among other benefits.

Who should not take spirulina?

Spirulina is generally considered safe. The Dietary Supplements Information Expert Committee (DSI-EC) has said that it does not pose a major risk to health. However, it may cause some side effects such as difficulty sleeping and problems with digestion.

People taking certain blood-pressure-lowering, immunosuppressant, or cholesterol-lowering medications, may need to avoid spirulina due to the potential for interaction with certain chemicals in spirulina.

Always check with a doctor that spirulina is safe for you to use, follow any instructions with care, and obtain your supplements from a reputable source. Some products may be contaminated with heavy metals and other toxins or bacteria.

Learn more about the side effects and risks of spirulina.

Is it good to take spirulina every day?

Most people who use spirulina take up to 10 grams every day for up to 6 months. A doctor can advise on how often to use it, how much to take, and for how long.

Spirulina is a type of cyanobacteria — often referred to as blue-green algae — that is highly nutritious.

Studies show that it may improve cholesterol and triglyceride levels, suppress oxidation, reduce blood pressure, and lower fasting blood sugar levels. However, more research is needed.

If you want to give this supplement a try, it’s widely available in stores and online.