Spirulina Research Analysis

Frank, Kurtis; Patel, Kamal; Lopez, Gregory; Willis, Bill

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Spirulina

Spirulina is a non-toxic blue-green algae. It's rich in nutrients and may have some general cardiovascular and anti-aging benefits. Its potentially potent immunomodulating properties may give it additional uses such as ameliorating allergies and asthma, but more research is needed.

Research analysis led by Wyatt Brown and reviewed by the Examine team.
Last Updated: Sep 3, 2021

Summary of Spirulina

Primary information, health benefits, side effects, usage, and other important details

What is spirulina?

Spirulina is a type of non-toxic blue-green algae (cyanobacteria). It may refer to a number of different species in the Arthrospira genus, namely platensis and maxima. Spirulina is often used as a vegan source of protein and iron and is rich in a variety of other nutrients and phytochemicals. It is believed by some to provide vitamin B12, but it actually contains the dubious pseuodovitamin B12 which hasn't been shown to be effective. Spirulina has a few notable active components. The main ingredient is called phycocyanobilin, which makes up about 1% of spirulina. This compound mimics the body’s bilirubin compound, in order to inhibit an enzyme complex called nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. By inhibiting NADPH oxidase, spirulina provides potent antioxidative and anti-inflammatory effects.

What are spirulina's benefits?

Evidence suggests a general improvement in the basic components of the lipid panel: triglycerides, HDL, LDL, VLDL, and total cholesterol. It seems to reduce blood pressure by a small amount, and may have some meaningful effects on liver enzymes and overall liver health, though more research is needed on that. It also seems to improve general antioxidant status and reduce markers of oxidative stress, as well as some inflammatory markers. When people take spirulina, they tend to lose a small amount of weight, even if they're not trying to, and there's some evidence to suggest that it can help regulate appetite.

Because of its potentially potent immunomodulating properties, spirulina may have utility for preventing allergic reactions and treating asthma. However, there's only a small amount of research for these indications. Another possible benefit is improved athletic performance, with both resistance and endurance exercise, but the evidence is still preliminary.

What are spirulina's side-effects and drawbacks?

While most spirulina products are safe, there have been reports of contamination with toxic microcystins from other bacteria. It is advisable to ensure that any spirulina products have been throughly tested for safety before consumption. In general, spirulina is safe and adverse events aren't common in clinical trials.

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How to Take

Recommended dosage, active amounts, other details

The dose of spirulina used in studies examining its effects vary greatly. In general, 1-8 g per day of spirulina has been shown to have some effect. The specific doses depend on the condition its being used for:

For cholesterol, doses in the range of 1-8 g per day may be impactful
For muscle performance, doses of 2-7.5 g per day have been used
For blood glucose control, very mild effects have been seen with 2 g per day
Blood pressure may be affected at doses of 3.5-4.5 g per day
Effects for fatty liver have been seen at doses of 4.5 g per day

Spirulina is about 20% C-phycocyanin by weight, and about 1% phycocyanobilin by weight. The dosage range of 200mg/kg C-phycocyanin (1g/kg spirulina) converted to human equivalent doses from rats is approximately:

11.0g for a 150lb person
14.5g for a 200lb person
18.2g for a 250lb person

Further research is needed to determine whether spirulina should be taken once a day, or in smaller doses, multiple times per day.

It is not recommended to exceed the highest dose mentioned above, as no clear benefits have been noted beyond that level.

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Human Effect Matrix

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The Human Effect Matrix summarizes human studies to tell you what effects Spirulina has on your body, how much evidence there is, and how strong these effects are.
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Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
Triglycerides	Notable	Very High See all 18 studies	In populations with metabolic syndrome or related morbidities (diabetes, hyperlipidemia, hypertension, etc.) spirulina in a variety of doses between 1-8g daily is able to reduce triglycerides up to 10-15%. For people without elevated cardiovascular risk factors, there may be some effect as well, though less pronounced.
HDL	Minor	Very High See all 16 studies	A positive influence of spirulina on HDL-C appears to be present, but the magnitude of benefit is not overly remarkable and varies depending on the disease state (with states associated with fatty liver having a much greater increase in HDL-C seen with spirulina)
LDL	Minor	Very High See all 16 studies	Degree of efficacy seems variable and correlated with disease state (more drastic improvements when LDL-C is much higher) but currently does not appear to be overly remarkable unless fatty liver exists.
Total cholesterol	Minor	Very High See all 16 studies	Reductions in cholesterol seen are positive, but not overly remarkable
General Oxidation	Notable	Very High See all 4 studies	More research is needed, but from what we have, it appears that a moderate beneficial effect is likely.
Interleukin 2	Notable	Very High See all 3 studies	A notable increase overall has been found in one meta-analysis.
Blood Pressure	Minor	Moderate See all 8 studies	Insufficient evidence to fully evaluate the effects on blood pressure, but in the context of hypertension, a small but meaningful effect is likely.
Blood glucose	Minor	Very High See all 8 studies	Reductions in blood glucose seen are not overly remarkable but one meta-analysis found a small, statistically significant reduction.
Insulin	Minor	Very High See 2 studies	There's likely a decrease for people with metabolic syndrome, though the effect is small, and the number of studies is small as well.
Interleukin 6	Minor	Very High See all 5 studies	A small reduction has been found in one meta-analysis, though more research is needed to determine how consistent or potent it is.
Malondialdehyde (MDA)	Minor	Very High See all 4 studies	Studies have mostly found a reduction, but more research is needed to confirm its potency and reliability.
Waist circumference	Minor	Very High See all 5 studies	Some studies have found small reductions, but the research is inconsistent, and more is needed to determine its potency and reliability.
Weight	Minor	Very High See all 14 studies	Overall, a meta-analysis found a small but statistically significant reduction, with a greater effect from higher doses.
vLDL-C	Minor	Very High See 2 studies	A small reduction has been found in one meta-analysis, based on 5 trials.
HbA1c	-	Very High See all 3 studies	No apparent effect overall. More research specifically in poorly controlled diabetes is needed.
TNF-Alpha	-	Very High See all 4 studies	One meta-analysis failed to find an effect overall, with the research being highly inconsistent.
Allergies	Strong	Very High See 2 studies	Two studies found that spirulina is strongly effective in controlling allergies, with the symptoms of nasal discharge, sneezing, nasal congestion, and itching being reduced, and smell being improved. According to self-reports in one study, more than twice as many subjects in the spirulina group reported more than a 2-fold increase in satisfaction with treatment. In another study, it was comparable to or even more potent than the comparator pharmaceutical drug. More research is needed.
Nasal Congestion	Strong	Very High See 2 studies	The decrease in nasal congestion seen in the both studies was remarkably strong relative to placebo, and comparable to a comparator pharmaceutical drug in another study, both in regards to allergic rhinitis; it is not sure if this applies to other causes of nasal congestion.
Liver Enzymes	Notable	Very High See all 5 studies	Preliminary evidence suggests the reduction of liver enzymes correlates with the degree of liver damage somewhat, and this is notable since the reduction of liver fat seen is strongly effective at this moment in time.
Symptoms of Oral Cancer	Notable	- See study	The lesions were fully healed in 44% of the 1g spirulina group relative to 7% of the placebo; although no reference drug was used.
Adiponectin	Minor	Very High See 2 studies	Two studies found a small increase but neither was statistically significant.
Anti-Oxidant Enzyme Profile	Minor	Very High See all 5 studies	Although increases have been noted in glutathione peroxidase and superoxide dismutase, it is difficult to predict when it will be most effective and more research is needed.
Arsenic Poisoning	Minor	- See study	Somewhat effective, but requires more evidence; no reference drug was used to compare
Body Fat	Minor	High See all 4 studies	A small reduction has been found in most studies. More research is needed to determine when and how it's most useful.
Fat Oxidation	Minor	- See study	Nothing remarkable in the one study on fat oxidation rates during exercise.
Insulin Sensitivity	Minor	- See study	Requires more evidence to establish its potency
Lipid Peroxidation	Minor	Very High See all 4 studies	Studies have mostly found a reduction, but more research is needed to confirm its potency and reliability.
Muscular Endurance	Minor	Moderate See all 3 studies	Studies currently assessing the effects of spirulina on muscular endurance are too hetereogeneous to properly assess potency thereof. However, a positive effect does appear to exist
Power Output	Minor	Very High See all 4 studies	Improvements have been seen during various types of training, the one negative study being on rowing power. More research is needed to determine any contexts which it might reliably work for.
Risk of Anemia	Minor	- See study	Although there was some promising evidence, it did not appear overly remarkable and requires further evidence.
White Blood Cell Count	Minor	Very High See 2 studies	Minor increase, needs more evidence in a non-aged cohort to assess potency
Red Blood Cell Count	-	- See study	Currently insufficient evidence to support a change in RBC count.
Liver Fat	Strong	- See study	Although only based on a series of case studies at this moment in time, the reduction of liver fat seen after 3 months was remarkably effective
C-Reactive Protein (CRP)	Notable	- See study	One study found a reduction.
Endothelin-1	Notable	- See study	One study found a notable effect.
Forced Expiratory Volume	Notable	- See study	One study found an increase comparable to medication.
Forced Vital Capacity	Notable	- See study	One study found an increase comparable to medication.
Interleukin 1-alpha	Notable	- See study	One study found a notable reduction.
Interleukin 1-beta	Notable	- See study	One study found a notable reduction.
Interleukin 10	Notable	- See study	One study found a notable increase.
Interleukin 4	Notable	Very High See 2 studies	Two studies found a notable reduction overall.
Natural Killer Cell Activity	Notable	- See study	NK cell activity against a tumor cell line (K562) increased 40% following a week ingestion of fairly reasonable oral dosing, suggesting that this is a notable increase of possible interest.
Natural Killer Cell Content	Notable	Very High See 2 studies	The increases in mRNA content of natural killer cell content increased 37-55% (NKG2D) and 75% (perforin) which appeared to be dose-dependent, a possibly potent immunostimulatory effect.
Sustained Virologic Response	Notable	- See study	Notably effective as it trended to outperform Milk Thistle, which is a good reference supplement in regards to a sustained virologic response (not the best comparison, however)
Appetite	Minor	High See all 3 studies	There may be a small reduction in some cases, but more research is needed to know when this occurs.
Arterial Stiffness	Minor	- See study	One study found a reduction.
CD4 Lymphocytes	Minor	- See study	One study found a non-significant reduction in chemotherapy.
CD8 Lymphocytes	Minor	- See study	There was a reduction in one study in chemotherapy
Cognition	Minor	- See study	One study found an improvement in mathematical ability.
Hemoglobin	Minor	High See all 3 studies	A small increase has been found more often than not.
IGF-1	Minor	- See study	One study found an increase.
Immunoglobulin G	Minor	- See 2 studies	A reduction for cancer patients undergoing chemotherapy and increase in healthy, elderly participants. More research is needed in both contexts.
Immunoglobulin M	Minor	- See study	One study found a reduction but it wasn't statistically significant.
Interferon Gamma	Minor	Moderate See 2 studies	Mixed evidence. The reduction in allergic rhinitis patients is quite notable, however.
Joint Pain (General)	Minor	- See study	One study found a reduction.
Muscle Soreness	Minor	- See study	An initial reduction in the 24 hours after exercise but an increase after that.
Myostatin	Minor	- See study	One study found a reduction.
Neutrophil Count	Minor	- See study	One study found different effects in different cycles of chemotherapy.
Oxygen Uptake	Minor	- See study	One study found a reduction during submaximal exercise.
P-Selectin	Minor	- See study	One study found an increase.
Peak Expiratory Flow Rate	Minor	- See study	One study found an increase, though it was smaller than for medication.
Plasma Vitamin C	Minor	- See study	One study found an increase.
Sprint Performance	Minor	- See study	One study found an increase.
Stress	Minor	Very High See 2 studies	A couple of studies have found a reduction. More research is needed.
Superoxide Dismutase Activity	Minor	- See study	One study found an increase.
Total antioxidant capacity (TAC)	Minor	High See all 3 studies	Two out of 3 studies found an increase.
Treg Cells	Minor	- See study	One study found a reduction post-exercise.
VO₂ Max	Minor	- See study	One study found an increase.
sE-Selectin	Minor	- See study	One study found a reduction.
sVCAM-1	Minor	- See study	One study found a reduction.
Aerobic Exercise	-	- See study	No apparent effect in one study.
Anxiety	-	- See study	No apparent effect in one study.
Bilirubin	-	- See study	No apparent effect in one study.
Blood Clotting	-	- See study	No apparent effect in one study.
Blood Lactate (Excercise)	-	- See study	No apparent effect in one study.
Circulating Alkaline Phosphatase	-	- See study	No apparent effect in one study.
Complement Component 3	-	Moderate See 2 studies	Mixed evidence in two studies.
Complement Component 4	-	- See study	No apparent effect in one study.
Creatine Kinase	-	- See study	No apparent effect in one study.
Creatinine	-	- See study	No apparent effect in one study.
Cytotoxic T Lymphocytes	-	- See study	No apparent effect in one study.
Day-Time Dysfunction	-	- See study	No apparent effect in one study.
Depression	-	- See study	No apparent effect in one study.
Endurance Training	-	High See all 3 studies	One study found an improvement but the overall evidence is inconsistent and unclear.
Fatigue	-	Very High See 2 studies	Currently no evidence to support an improvement in fatigue symptoms
Follistatin	-	- See study	No apparent effect in one study.
Gamma Delta T Cells	-	- See study	No apparent effect in one study.
Glutathione (GSH)	-	- See study	No apparent effect in one study.
Glutathione Reductase	-	- See study	No apparent effect in one study.
Heart Rate	-	- See 2 studies	Mixed evidence during exercise.
Hip Circumference	-	Moderate See 2 studies	Inconsistent evidence from two studies. More research is needed.
Immunoglobulin A	-	Very High See 2 studies	No apparent effect.
Insulin Resistance	-	- See 2 studies	Mixed evidence, more research is needed.
Lean Mass	-	Moderate See 2 studies	No apparent effect overall.
Macrophage Inhibitory Cytokine 1	-	- See study	No apparent effect in one study.
Monocyte Chemoattractant Protein-1	-	- See study	No apparent effect in one study.
Nesfatin-1	-	- See study	No apparent effect in one study.
Omentin-1	-	- See study	No apparent effect in one study.
Oxygenation Cost of Exercise	-	- See study	No apparent effect in one study.
Respiratory Exchange Ratio	-	- See study	No apparent effect in one study.
Respiratory Quotient	-	- See study	No apparent effect in one study.
Serum Albumin	-	- See study	No apparent effect in one study.
Serum Platelets	-	Moderate See 2 studies	One study found an increase while another one didn't find an effect.
Sleep Disturbances	-	- See study	No apparent effect in one study.
Sleep Duration	-	- See study	No apparent effect in one study.
Sleep Efficiency	-	- See study	No apparent effect in one study.
Sleep Latency	-	- See study	No apparent effect in one study.
Sleep Quality	-	- See study	No apparent effect in one study.
Sperm Count	-	- See study	No apparent effect in one study.
Sperm Quality	-	- See study	No apparent effect in one study.
Urea	-	- See study	No apparent effect in one study.
Vascular Endothelial Growth Factor	-	- See study	No apparent effect in one study.
Waist-Hip Ratio	-	Very High See 2 studies	No apparent effect in two studies.
sICAM-1	-	- See study	No apparent effect in one study.

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Frequently Asked Questions and Articles on Spirulina

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Things to Note

Is a Form Of

Primary Function:

General Health

Other Functions:

Caution Notice

Some users may possess allergies to spirulina (infrequent)

May interact with enzymes of drug metabolism

An allergic reaction to spirulina has been reported, although overall frequency of allergic responses or cross-sensitivities are not yet known
Preliminary evidence has suggested a reduction in the activities of the enzymes CYP2C6, CYP1A2, and CYP2E1
The same evidence has noted an upregulation (increase in activity) for both CYP2B1 and CYP3A1

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Spirulina

Spirulina is a non-toxic blue-green algae. It's rich in nutrients and may have some general cardiovascular and anti-aging benefits. Its potentially potent immunomodulating properties may give it additional uses such as ameliorating allergies and asthma, but more research is needed.

Summary of Spirulina

Primary information, health benefits, side effects, usage, and other important details

What are spirulina's benefits?

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Guidance from the experts

How to Take

Recommended dosage, active amounts, other details

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Human Effect Matrix

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Study Deep Dives

Frequently Asked Questions and Articles on Spirulina

Things to Note

Is a Form Of

Primary Function:

Other Functions:

Caution Notice

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Research Breakdown on Spirulina

1.1History

1.2Sources

1.3Properties

1.4Biological Activity

2.1Toxicity

2.2Side Effects and Adverse Events

2.3Degradation, Adulteration, Contamination

3.1Mineral Detoxification

3.2Phase I Enzyme Interactions

3.3Drug-Drug Interactions

5.1Mechanisms

5.2Neuroprotection and Cognitive Decline

5.3Neurogenesis

5.4Motor Neurons

5.5Depression

6.1Cardiac Function

6.2Hemodynamics

6.3Lipid and Cholesterol Absorption

6.4Blood Lipids and Lipoproteins

7.1Insulin Sensitivity

7.2Blood Glucose and Insulin

7.3Glycation

7.4Diabetes

8.1Mechanisms

8.2Interventions

9.1Mechanisms

9.2Natural Killer Cells

9.3Neutrophils

9.4Arthritis

9.5Allergies

9.6Interventions

10.1General

10.2Interventions

11.1Testosterone

11.2Leptin

12.1General Mutagenicity

12.2Immunological Interactions

12.3Oral

12.4Melanoma

12.5Colon

13.1Muscle Hypertrophy

13.2Power Output

13.3Endurance and Time to Exhaustion

13.4Chronic Fatigue

14.1Interventions

15.1Mechanisms (Hepatoprotection)

15.2Liver Enzymes

15.3Fibrosis

15.4Steatohepatitis (Fatty Liver)

15.5Virology

15.6Anemia

16.1Thymus

16.2Kidneys