Spirulina is a blue-green algae supplement made from Arthrospira platensis. It is valued for its protein content and antioxidant compounds such as phycocyanin.

What are the potential benefits of spirulina?

Spirulina may support antioxidant and anti-inflammatory activity, help improve some blood lipid markers, and modulate certain immune functions. Effects can vary by person and health status.

How much spirulina should I take?

Common supplemental amounts are about 1–3 g per day. Follow the product label and consider medical advice if you have health conditions or take medications.

Is spirulina a reliable source of vitamin B12?

Spirulina contains B12 analogs that may not be biologically active in humans. People relying on B12 should use a proven B12 supplement or fortified foods.

Are there safety concerns with spirulina?

Quality matters because contamination can occur in poorly controlled products. People who are pregnant, immunocompromised, or have autoimmune conditions should consult a clinician before use.

313 science-backed nutrients

3251 sources considered

Evidence-graded information

Explore by goal or category

Find a nutrient

313 nutrients total

Vitamin B

Vitamin B1 (Thiamine)

Vitamin B2 (Riboflavin)

Vitamin B3 (Niacin)

Vitamin B5 (Pantothenic Acid)

Vitamin B6 (Pyridoxine)

Vitamin B7 (Biotin)

Vitamin B9 (Folic Acid)

Vitamin B12 (Methylcobalamin)

Vitamin B12 (Cobalamin)

Vitamin A & Carotenoids

Vitamin C

Vitamin D

Vitamin E

Vitamin K

Vitaminoids

Trimethylglycine (Betaine)

NMN (Nicotinamide Mononucleotide)

Pyrroloquinoline Quinone (PQQ)

D-Chiro-Inositol

Coenzym Q10 (Ubiquinone)

Betaine HCL

Nicotinamide Riboside

Vitamin B8 (Myo-Inositol)

Choline

Citicoline (CDP-Choline)

Coenzyme Q10 (Ubiquinol)

Calcium

Calcium Alpha-Ketoglutarate

Magnesium

Magnesium Bisglycinate

Magnesium L-Threonate

Trace Minerals

Copper (Bisglycinate)

Chromium Picolinate

Manganese (Bisglycinate)

Zinc

Pentadecanoic Acid (C15:0)

Phosphatidylserine

R-Alpha Lipoic Acid

Black Cumin Oil

Extra Virgin Olive Oil

Ceratiq wheat oil extract

Phospholipids

Algae Oil

Fish Oil

Conjugated Linoleic Acid

Gamma-Aminobutyric Acid

Alpha-Linolenic Acid

Gamma-Linolenic Acid

Omega-3

Docosapentaenoic acid (DPA)

Eicosapentaenoic acid (EPA)

Docosahexaenoic acid (DHA)

AminoMar

Acetyl-L-Carnitine

PABA (para-aminobenzoic acid)

Essential Amino Acids

Conditionally Essential Amino Acids

L-Theanine

Non-Essential Amino Acids

Beta-Alanine

L-Cysteine Hydrochloride

Amino Acid Derivative

Taurine

Creatine (Hydrochloride)

L-Arginine Alpha-Ketoglutarate

Creatine (Monohydrate)

Akkermansia muciniphila

Lactobacillus Reuteri

Probiotics

Bifidobacterium longum BB536

Prebiotics

Stinging Nettle Extract

Pomegranate Polyphenols

Red Beet Extract

Pine Extract (Pycnogenol)

Oligomeric Proanthocyanidins (OPC)

Ashwagandha Root Extract

Methylsulfonylmethane (MSM)

Citrus Sinensis Extract

Horsetail Stem Extract

Flax Seed Extract

Sulforaphane Glucosinolate

Garlic Extract

Black Pepper

Apricot Kernel Extract

Lovage

Spiny Rest Harrow Root Extract

Juniper Berry Extract

Bearberry Leaf Extract

White Kidney Bean Extract

Lady’s Mantle Extract

Bitter Orange Extract

St. John’s Wort Extract

Japanese Knotweed Extract

Hydroxytyrosol/tyrosol

Olive extract

Sesame seed lignan extract

Broccoli Sprout Extract

Cranberry Extract

Flavon Glycosides

Gentian Root Extract

Griffonia simplicifolia Extract

Ajuga Turkestanica Extract

Amaranthus Leaf Extract

Banaba Extract

Boswellia Extract

Capsaicin

Cayenne Pepper Extract

Celery Extract

Ceylon Cinnamon Extract

Chamomile Extract

Charantin

Chinese Goldthread Root Extract

Citrus Aurantium Extract

Cocoa Extract

Cyanotis Arachnoidea Extract

Fadogia Agrestis Extract

Garcinia Cambogia Extract

Goldenrod Extract

Green Tea Extract

Guarana Extract

Horse Chestnut Extract

Grapefruit Seed Extract

Grape Vine Leaf Extract

Green Tea Polyphenols

Epigallocatechin Gallate (EGCG)

Adaptogens

Cordyceps sinensis extract

Ginsenoside

Lion's Mane (Hericium erinaceus)

Ginseng Extract

Cat's Claw (Uncaria tomentosa)

Arjuna (Terminalia arjuna)

Tribulus Terrestris Extract

Rhodiola rosea

Panax Ginseng Extract

Mushrooms

Reishi Extract

Astragalus Polysaccharides

Hyaluronic Acid

Glucosamine Sulfate

Chondroitin Sulfate

Glucosamine Sulphate 2KCL

Spirulina

Moderate study situation·7/10

A higher score indicates better study conditions, but not necessarily effectiveness.

Spirulina is a nutrient-dense blue-green algae supplement valued for antioxidant, cardiovascular, and immune benefits.

Anti-inflammatory Cardiovascular Support Essential Nutrient Antioxidant Immune Booster Cholesterol Management Energy Support

dose range

1–3 g

Once or twice daily with meals.

Consumption

Take with meals to enhance absorption and reduce risk of GI discomfort.

Not fat-soluble.

Best time

Morning or with main meals; split dosing may enhance tolerance.

Description

Spirulina is a blue-green algae (Arthrospira platensis) cultivated as a dietary supplement for its high protein, vitamin, mineral, and antioxidant content. It is commonly used to support overall wellness, particularly among those seeking plant-based nutrition.

benefits

Main effects with level of evidence

Moderate

Note on evidence

Human clinical trials support some benefits, particularly for cholesterol and inflammation, but evidence is limited for some other claims and long-term safety data are incomplete.

Antioxidant and Anti-Inflammatory Effects

Moderate

Contains phycocyanin and other antioxidants that help reduce oxidative stress and inflammatory markers in people with metabolic syndrome and related conditions.

Particularly relevant for: General public · People with inflammatory conditions

S1 · PubMed Review: Spirulina and Human Health S3 · NIH NCCIH Fact Sheet: Spirulina S5 · Examine.com: Spirulina Evidence Summary

Cholesterol and Heart Health Support

Moderate

Supplementation may lower LDL cholesterol, triglycerides, and may modestly increase HDL cholesterol, promoting cardiovascular health, particularly in those with dyslipidemia.

Particularly relevant for: Adults with high cholesterol · Individuals seeking cardiovascular support

S2 · PubMed Meta-Analysis: Spirulina Effects on Serum Lipids S1 · PubMed Review: Spirulina and Human Health S5 · Examine.com: Spirulina Evidence Summary

Immune System Modulation

Limited

May enhance certain aspects of immune function, such as antibody production and natural killer cell activity, but clinical effect sizes vary across populations.

Particularly relevant for: Adults seeking immune support · Vegetarians/vegans

S1 · PubMed Review: Spirulina and Human Health S3 · NIH NCCIH Fact Sheet: Spirulina

Nutritional Support

Moderate

Provides easily absorbable protein, vitamins (B12 analogs), and minerals, supporting dietary needs especially in vegetarian or vegan diets.

Particularly relevant for: Vegetarians · Vegans · General public

S3 · NIH NCCIH Fact Sheet: Spirulina S5 · Examine.com: Spirulina Evidence Summary

Safety & Information

Important safety information & known risks

For educational purposes only • not medical advice

Generally safe if sourced from reputable manufacturers, but contamination and certain underlying health risks must be considered.

warning notices

May cause nausea, diarrhea, or mild GI upset in some users.
Potential for contamination with heavy metals or microcystins; always select certified products.
Should not be used in individuals with PKU due to high phenylalanine content.
Avoid use in autoimmune disorders unless supervised by a clinician.
Avoid if you have phenylketonuria (PKU) due to high phenylalanine content.
Do not use if you have autoimmune diseases unless under clinical supervision.
Avoid during pregnancy or breastfeeding due to insufficient safety data.
Use only products tested for microcystin and heavy metal contamination.
Consult a healthcare provider before use if taking immunosuppressive or anticoagulant medications.

Known interactions with medications

immunosuppressants
anticoagulants

Contraindications / special precautions

Phenylketonuria (PKU)
Pregnancy and breastfeeding
Autoimmune disorders

interactions

Important interactions between active ingredient ↔ supplement / medication / food

Spirulina may interact with certain medications and nutrients, primarily via immune, metabolic, or anticoagulant effects.

May counteract immunosuppressive therapy.

drug · immunosuppressive drugs

CautionModerate

Why

Spirulina can enhance immune function, which may interfere with medications intended to suppress immune activity.

recommendation

Discuss with your healthcare provider before combining spirulina with immunosuppressants.

S3 · NIH NCCIH Fact Sheet: Spirulina S1 · PubMed Review: Spirulina and Human Health

May increase bleeding risk with anticoagulants.

drug · anticoagulant medications

CautionLimited

Why

Spirulina may have mild antiplatelet effects, potentially enhancing bleeding risk when combined with blood thinners.

recommendation

Monitor for bleeding; consult a clinician before co-administration.

S4 · EFSA: Scientific Opinion on the Safety of Spirulina S3 · NIH NCCIH Fact Sheet: Spirulina

mechanisms of action

Brief explanations of how it works

Antioxidant Activity via Phycocyanin

Phycocyanin and other polyphenols in spirulina scavenge free radicals and reduce lipid peroxidation, protecting cells against oxidative stress.

S1 · PubMed Review: Spirulina and Human Health S5 · Examine.com: Spirulina Evidence Summary

Modulation of Immune Responses

Polysaccharides and proteins in spirulina stimulate antibody production and activate immune cells, enhancing overall immune function.

S1 · PubMed Review: Spirulina and Human Health S3 · NIH NCCIH Fact Sheet: Spirulina

Lipid Profile Regulation

Spirulina may inhibit intestinal cholesterol absorption and modulate enzymes involved in lipid metabolism, leading to improved cholesterol profiles.

S2 · PubMed Meta-Analysis: Spirulina Effects on Serum Lipids S5 · Examine.com: Spirulina Evidence Summary

Sources & References

Primary literature and reviews on which these statements are based

6 sources

PubMed Review: Spirulina and Human Health

PubMed Meta-Analysis: Spirulina Effects on Serum Lipids

NIH NCCIH Fact Sheet: Spirulina

EFSA: Scientific Opinion on the Safety of Spirulina

Examine.com: Spirulina Evidence Summary

Cochrane Review: Spirulina Supplementation

Last updated: January 31, 2026

This information is for educational purposes only and does not replace medical advice.