Spirulina is a type of blue-green algae that people can take as a dietary supplement. People consider spirulina a superfood due to its nutritional content and potential health benefits. How much spirulina a person takes per day can vary.
Spirulina contains protein and vitamins, making it a suitable dietary supplement for people on vegetarian or vegan diets.
Research
This article discusses 13 potential health benefits people may get from adding spirulina to their diet.

Consuming spirulina is one way to supplement protein and vitamins in the diet.
According to the United States Department of Agriculture (USDA), one tablespoon or 7 grams (g) of dried spirulina
- 20.3 calories
- 4.02 g of protein
- 1.67 g of carbohydrate
- 0.54 g of fat
- 8.4 milligrams (mg) of calcium
- 2 mg of iron
- 13.6 mg of magnesium
- 8.26 mg of phosphorous
- 95.2 mg of potassium
- 73.5 mg of sodium
- 0.7 mg of vitamin C
It also contains thiamin, riboflavin, niacin, folate, and vitamins A, B6, and K.
Spirulina contains a range of antioxidants, including phycocyanin, a blue-green pigment.
Free radicals
Antioxidants, such as those in spirulina, may help fight free radicals and protect the body from cell damage.
Spirulina contains the antioxidant beta carotene. The body converts beta carotene into vitamin A, which plays a
In
The mice that consumed spirulina had better protection and less damage to the retina and photoreceptors in their eyes. This suggests spirulina might help protect eye health in humans, although more research is needed.
It is worth noting that nutrients vary between products, and products used in experiments may not be the same as those available to consumers. The spirulina product analyzed by the
Spirulina has shown promise for treating and preventing gum disease and other oral health problems.
In 2013,
Leukoplakia is a condition where lesions form in the mouth, usually due to tobacco use. Sometimes, it can become cancerous. In a small, older
Various algae types
A 2020
- body mass index (BMI)
- body fat
- waist circumference
- appetite
- blood lipids
One possible reason is that ingredients in spirulina prevent the small intestine from absorbing as much fat.
However, further research, including larger clinical trials, would be warranted to confirm these benefits.
Animal studies indicate spirulina may support gut health as people age. A
Spirulina does not contain much fiber, so people should eat it alongside other gut-healthful, high fiber foods.
More research is needed to confirm whether spirulina can benefit the gut health of humans.
Spirulina may help manage blood sugar levels, which is important for people with diabetes, although more research is needed.
A 2018
In a 2017 animal
- lower blood sugar
- higher insulin levels
- improved liver enzyme markers
The findings suggest that ingredients in spirulina could play a protective role in type 1 diabetes, but more research is needed.
Taking spirulina extract may help to lower cholesterol levels. High cholesterol levels can increase the risk of heart disease.
A 2016
In a 2013
As well as lowering cholesterol, spirulina may help manage blood pressure.
A small-scale 2016
High blood pressure and cholesterol levels are both linked to heart disease.
A 2018
Spirulina may help boost a person’s basal metabolism. A higher metabolic rate may increase the number of calories they burn, which may aid weight loss.
In a small-scale 2014
The participants all had nonalcoholic fatty liver disease, and more research is needed to see if spirulina may boost metabolism in others without this condition.
When a person has allergies to pollen, dust, or pets, the inside of their nose may swell. This reaction is called allergic rhinitis. There is some evidence that spirulina could help improve the symptoms of this condition.
A 2013
- runny nose
- sneezing
- nasal congestion
- itching
In 2020,
In some places, there is a risk of poisoning from contaminated drinking water and other sources of pollutants. In 2006, some
In 2016, a review found evidence of antitoxic properties in spirulina that could make it useful alongside other treatments for counteracting pollutants, such as:
The authors suggested that spirulina could support clinical treatment in cases of pollutant poisoning, but larger studies are needed to confirm this.
A 2018 paper suggests spirulina could play a role in treating mood disorders.
The theory is that spirulina is a source of tryptophan, an amino acid that supports serotonin production. Serotonin plays an important role in mental health.
Depression, anxiety, and other mental health conditions can involve low levels of serotonin. Taking tryptophan supplements to maintain serotonin levels could help support mental well-being.
However, more studies are needed.
People should speak with a doctor or another healthcare professional before using spirulina to boost their physical or mental well-being.
Spirulina is a blue-green algae product.
According to the National Institutes of Health (NIH), people have used doses of up to 19 g per day for a maximum of 2 months and up to 10 g per day for a maximum of 6 months.
People should not exceed the dose stated on the product label.
Research has not confirmed a safe upper limit for taking spirulina, but the NIH notes that taking too much can lead to:
- nausea
- vomiting
- diarrhea
- headache
- dizziness
The Food and Drug Administration (FDA) does not regulate spirulina, and some
These can lead to liver damage, vomiting, weakness, a rapid heartbeat, shock, and possibly death.
Spirulina may not be safe to use:
- during pregnancy
- for children
- with autoimmune diseases such as multiple sclerosis and rheumatoid arthritis, as it can increase immune activity
- before or after surgery, as it may affect blood glucose levels
Before taking spirulina, people should talk with a doctor to ensure it will not interact with other drugs and that it is safe for them to use.
They should also obtain spirulina and other supplements from a reputable source and ensure that the product has undergone safety testing.
The FDA has previously issued warnings about misleading claims for products sold online that contain spirulina.
There have also been some cases of allergic reactions to spirulina. An allergic reaction can sometimes lead to anaphylaxis, a life threatening health condition that can result in anaphylactic shock. Anyone who experiences swelling, hives, or difficulty breathing after consuming spirulina needs immediate medical attention.
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Spirulina is available in powder or tablet form.
As a powder, people can:
- add it to smoothies, which gives the drink a green color
- sprinkle spirulina powder on salads or in soups
- mix it into energy balls with other healthy ingredients
- stir a tablespoon into fruit or vegetable juices
People can also take spirulina as a dietary supplement in tablet form.
Here are some questions people often ask about spirulina:
What does spirulina do to the body?
How does spirulina affect weight?
Is spirulina safe?
A person should always buy from a reputable source, check it has undergone testing, and follow the instructions on the label. It may not be safe during pregnancy, for children, and for those with an autoimmune disease. Some studies have found contamination in spirulina products, which could be dangerous.
Spirulina contains a range of nutrients and antioxidants that may make it suitable for treating or preventing various diseases.
However, more research is needed before doctors can recommend spirulina to treat any health condition.
Anyone interested in using spirulina as a supplement should first speak with a doctor. They should ensure they only purchase products from a reputable source, as there is a risk of contamination.