Spirulina is incredibly good for you.
It is loaded with nutrients that can have powerful effects on your body and brain.
Here are 10 evidence-based health benefits of spirulina.
Spirulina is an organism that grows in both fresh and salt water.
It is a type of bacteria called cyanobacterium, which is often referred to as blue-green algae.
Just like plants, cyanobacteria can produce energy out of sunlight, via the process called photosynthesis.
Spirulina was consumed by the Aztecs back in the day, but became popular again when NASA proposed that it could be grown in space and used by astronauts (1).
A standard daily dose of spirulina is 1-3 grams, but doses of up to 10 grams per day have been used effectively.
It is actually quite amazing how nutritious it is.
A single tablespoon (7 grams) of dried spirulina powder contains (2):
- Protein: 4 grams.
- Vitamin B1 (Thiamin): 11% of the RDA.
- Vitamin B2 (Riboflavin): 15% of the RDA.
- Vitamin B3 (Niacin): 4% of the RDA.
- Copper: 21% of the RDA.
- Iron: 11% of the RDA.
- It also contains decent amounts of magnesium, potassium and manganese, and small amounts of almost every other nutrient that we need.
Gram for gram, this means that spirulina may literally be the single most nutritious food on the planet.
A tablespoon of spirulina contains a small amount of fat (around 1 gram), including both omega-6 and omega-3 fatty acids in about a 1.5:1 ratio.
The quality of the protein in spirulina is considered excellent, comparable to eggs. It contains all the essential amino acids that we need.
Bottom Line: Spirulina is a type of blue-green algae that grows in both salty and fresh water. It may be the single most nutrient-dense food on earth.
Oxidative damage can harm our DNA and cells.
This damage can drive chronic inflammation, which contributes to cancer and other diseases (5).
Spirulina is a fantastic source of antioxidants, which can protect against oxidative damage.
The main active component is called phycocyanin. This antioxidant substance also gives spirulina its unique blue-green color.
Bottom Line: Phocyanin is the main active compound in spirulina. It has powerful antioxidant and anti-inflammatory properties.
Heart disease is currently the world's biggest killer.
It is known that many measurable factors, termed risk factors, are linked to an increased risk of heart disease.
As it turns out, spirulina has been shown to have beneficial effects on many of them.
For example, it can lower total cholesterol, LDL cholesterol and triglycerides, while raising HDL (the "good") cholesterol.
In a study of 25 people with type 2 diabetes, 2 grams per day of spirulina significantly improved these markers (9).
Another study in people with high cholesterol found that 1 gram of spirulina per day lowered triglycerides by 16.3% and LDL by 10.1% (10).
Bottom Line: Studies have shown that spirulina can lower triglycerides and LDL cholesterol, and sometimes may raise HDL (the "good") cholesterol.
Fatty structures in the body are susceptible to oxidative damage.
In a study of 37 individuals with type 2 diabetes, 8 grams of spirulina per day significantly reduced markers of oxidative damage. It also increased levels of antioxidant enzymes in the blood (18).
Bottom Line: Fatty structures in the body can become oxidized, which drives the progression of many diseases. The antioxidants in spirulina can help prevent this from happening.
Some evidence suggests that spirulina can have anti-cancer properties.
Spirulina has been particularly well studied with regard to oral cancer, which is cancer of the mouth.
One study looked at the effects of spirulina on 87 people from India with precancerous lesions called OSMF in the mouth.
After using 1 gram per day for 1 year, 45% of the spirulina group had a complete regression of lesions in the mouth, compared to only 7% in the control group (21).
When they stopped taking the spirulina, almost half of the responders developed these lesions again the following year.
In another study of 40 subjects with OSMF precancerous lesions, 1 gram of spirulina per day led to greater improvement in symptoms than the drug Pentoxyfilline (22).
Bottom Line: Spirulina may have some anti-cancer properties, especially against a type of precancerous lesion called OSMF (oral submucous fibrosis).
High blood pressure is an important driver of many killer diseases.
This includes heart attacks, strokes and chronic kidney disease.
This is thought to be driven by an increased production of nitric oxide, a signalling molecule that helps the blood vessels relax and dilate (23).
Bottom Line: In one study, a higher dose of spirulina has been shown to lead to lower blood pressure levels, a major risk factor for many diseases.
Allergic rhinitis is characterized by inflammation in the nasal airways.
It is triggered by environmental allergens, such as pollen, animal hair or even wheat dust.
Spirulina is a popular alternative treatment for symptoms of allergic rhinitis, and there is evidence that it can be effective (24).
In one study of 127 people with allergic rhinitis, 2 grams per day dramatically reduced symptoms like nasal discharge, sneezing, nasal congestion and itching (25).
Bottom Line: Spirulina supplements have been shown to be very effective against allergic rhinitis, helping to reduce various symptoms.
There are many different forms of anemia.
The most common one is characterized by a reduction in hemoglobin or red blood cells in the blood.
Anemia is fairly common in the elderly, leading to prolonged feelings of weakness and fatigue (26).
In a study of 40 older people with a history of anemia, spirulina supplementation increased the hemoglobin content of red blood cells. Immune function also improved (27).
However, this is just one study, and more research is needed before any recommendations can be made.
Bottom Line: One study shows that spirulina may be effective against anemia in the elderly. More research is needed.
Exercise-induced oxidative damage is a major contributor to muscle fatigue.
Certain plant foods have antioxidant properties that can help athletes and physically active individuals minimize this damage.
Spirulina appears to be beneficial, with some studies showing improved muscle strength and endurance.
Another study in college athletes found that spirulina supplementation increased muscle strength, but did not have any effect on endurance (30).
Bottom Line: Some studies have shown that spirulina supplementation can enhance endurance, and one study shows that it can increase muscle strength.
Animal studies have shown that spirulina can significantly lower blood sugar levels.
There is also some evidence that spirulina can be effective in humans.
In a study of 25 patients with type 2 diabetes, 2 grams of spirulina led to an impressive reduction in blood sugar levels (9).
HbA1c, a marker for long-term blood sugar levels, decreased from 9% to 8%, which is substantial. Studies estimate that a 1% reduction in this marker can lower the risk of diabetes-related death by 21% (34).
However, this study was small and only lasted for 2 months, so take this with a grain of salt.