Spirulina

Nutrient-dense blue-green algae providing complete protein, antioxidants, and essential nutrients

Scientific nameSpirulina platensis/maxima FormulaComplex nutrients and proteins Molecular weightVariable biological compounds g/mol CASVarious natural compounds

85 absorption score

7 safety / 10

30 USD per month

5 documented interactions

Check it against something

Evidence level A

Spirulina with:

82 out of 100

Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Complete protein and amino acid profile

Provides all essential amino acids in highly bioavailable form

Contains 60-70% complete protein with excellent amino acid profile Evidence A-grade Immediate nutritional benefits

Enhanced immune system function

Supports immune response and may reduce infection risk

Rich in antioxidants, vitamins, and immunomodulatory compounds Evidence B-grade 2-8 weeks

Powerful antioxidant protection

Provides potent antioxidants including phycocyanin

High concentration of antioxidants neutralize free radicals Evidence B-grade 2-6 weeks

Energy and endurance support

May improve energy levels and physical performance

Rich in B vitamins, iron, and other energy-supporting nutrients Evidence B-grade 1-4 weeks

Cholesterol and heart health support

May help reduce cholesterol and support cardiovascular health

Antioxidants and nutrients support healthy cholesterol levels Evidence C-grade 4-12 weeks

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

Probiotics for Autoimmune Disease Support Gut health & immune modulation 10-100 billion CFU daily B 60% Turmeric Anti-inflammatory & antioxidant 300-1000mg A 3% Vitamin D3 Bone health & immune support 1000-2000 IU A 85% Glutathione Master antioxidant & detox support 250-750mg B 20% Astaxanthin Superior antioxidant & skin protection 4-12mg B 20% Zinc Picolinate Superior immune & healing support 15-30 mg A 95%

Every pair we checked

12 combinations scored by the engine

Spirulina + Caffeine No documented interaction either way No known interaction 70

Spirulina + Creatine Monohydrate No documented interaction either way No known interaction 70

Spirulina + Calcium Carbonate No documented interaction either way No known interaction 70

Spirulina + Whey Protein No documented interaction either way No known interaction 70

Spirulina + Lactase No documented interaction either way No known interaction 70

Spirulina + Bovine Collagen No documented interaction either way No known interaction 70

Spirulina + DHA No documented interaction either way No known interaction 70

Spirulina + Turmeric No documented interaction either way No known interaction 70

Spirulina + Fish Oil (EPA/DHA) No documented interaction either way No known interaction 70

Spirulina + Lactobacillus acidophilus Enhanced gut health and nutrient absorption Works better together 75

Spirulina + Omega-3 + Curcumin + Vitamin D Triple Anti-Inflammatory Formula Enhanced anti-inflammatory and antioxidant effects Works better together 78

Spirulina + Vitamin D3 Enhanced iron absorption from spirulina Works better together 82

Dosage

With meals

Daily3-10g

Nutritional support3-6g daily

Athletic performance5-10g daily

Immune antioxidant3-6g daily

Therapeutic10-15g daily (short-term)

Before you take it

VeganYes

When to expect it

First Effects1-2 weeks for energy and nutritional benefits

Peak Benefits4-12 weeks for sustained immune and antioxidant benefits

Deficiency DevelopmentReturn to baseline nutrition levels when stopped

Toxicity OnsetRare with quality products, risk with contaminated sources

How to measure it

$100-200

MarkerComplete blood count, protein status, or antioxidant markers

OptimalImproved nutritional markers and antioxidant status

Deficient belowNot applicable for supplement

FrequencyEvery 6-12 months for nutritional monitoring

What people actually reported to the FDA

CAERS, 29 reports naming it as the suspect

Most reported effects

Vomiting 8

Dyspnoea 5

Headache 5

Malaise 5

Convulsion 3

Named as the suspect 29 reports of 51 that mention it at all

Serious outcome 81% hospitalisation, emergency room or worse

Other Serious or Important Medical Event12

Hospitalization11

Visited Emergency Room9

Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →

What actually reaches you

The label counts the carrier, your body does not

Absorption Very high 85 of 100 · best absorbed form of this compound

Delivered daily 5525 mg

Cost per 100 mg delivered $0.02 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented

Vitamin C

Enhanced iron absorption from spirulina

Vitamin C improves non-heme iron bioavailability · level A

Omega 3 Fatty Acids

Enhanced anti-inflammatory and antioxidant effects

Complementary anti-inflammatory pathways · level B

Probiotics

Enhanced gut health and nutrient absorption

Spirulina may support beneficial gut bacteria · level C

What not to take with Spirulina

2 documented

Immunosuppressive Drugs

May counteract immunosuppressive effects

Spirulina stimulates immune function · moderate significance

Blood Thinners

May enhance anticoagulant effects

Contains compounds that may affect blood clotting · mild significance

Medication interactions

Discuss these with a pharmacist before combining

immunosuppressive-medications Moderate

May reduce effectiveness of immunosuppressive drugs

What to do: Avoid in organ transplant patients

diabetes-medications Minor

May affect blood sugar levels

What to do: Monitor blood glucose

phenylketonuria-diet Major

Contains phenylalanine

What to do: Contraindicated in PKU

Available forms

bioavailability compared

Organic Spirulina Powder/Tablets 85

Organic Spirulina Powder/Tablets: Complete protein, Nutrient dense, Antioxidant rich, Sustainable

Food sources

before you supplement

Spirulina powder Pure concentrated form · 85

Spirulina tablets Convenient dosing form · 80

Fresh spirulina (rare) Highest nutrient density · 90

Green superfood blends Variable spirulina content · 75

Too little

deficiency signs

Not essential - but symptoms addressed by spirulina:
Protein deficiency and poor amino acid status
Low energy and fatigue
Poor immune function and frequent infections
Nutritional deficiencies (iron, B vitamins, etc.)
Oxidative stress and cellular damage
Poor exercise performance and recovery

Too much

toxicity signs

Generally safe but potential concerns:
Heavy metal toxicity from contaminated sources
Autoimmune flares in susceptible individuals
Digestive upset and nausea
Allergic reactions in sensitive individuals

Who benefits most

vegetarians-vegans

Excellent plant-based complete protein and B12 source

3-10g daily

athletes-performance

Provides complete protein and energy-supporting nutrients

5-10g daily

immune-support

Rich in antioxidants and immune-supporting compounds

3-6g daily

nutritional-deficiency

Provides concentrated nutrition for those with poor diets

3-10g daily

antioxidant-support

High concentration of unique antioxidants like phycocyanin

3-6g daily

Where to buy it

compare forms first

Look for Spirulina at 3-10g per serving. The form that matters here is Organic Spirulina Powder/Tablets.

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How it works

Provides complete protein with all essential amino acids
Rich in antioxidants including phycocyanin, beta-carotene, and chlorophyll
Contains immune-modulating polysaccharides and glycolipids
Provides concentrated vitamins, minerals, and essential fatty acids
Supports detoxification through chlorophyll and other compounds
May enhance nitric oxide production improving circulation

Key findings

what the evidence supports

Excellent source of complete protein and essential nutrients
Moderate evidence for immune support and antioxidant benefits
Generally safe but quality and source are critical
May be beneficial for vegetarians and those with poor nutrition

Sources: NIH Examine.com · data reviewed 2026-08-02

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Spirulina?

Documented effects: Complete protein and amino acid profile; Enhanced immune system function; Powerful antioxidant protection; Energy and endurance support. Provides all essential amino acids in highly bioavailable form

How much Spirulina should you take per day?

The common daily range is 3-10g. By goal — nutritional support: 3-6g daily; athletic performance: 5-10g daily; immune antioxidant: 3-6g daily; therapeutic: 10-15g daily (short-term).

When is the best time to take Spirulina?

With meals. First effects are typically reported within 1-2 weeks for energy and nutritional benefits.

What are the side effects of Spirulina?

At excessive doses: Generally safe but potential concerns:, Heavy metal toxicity from contaminated sources, Autoimmune flares in susceptible individuals, Digestive upset and nausea, Allergic reactions in sensitive individuals. Safety rating at normal doses is 7 out of 10.

What should you not take with Spirulina?

Separate it from Immunosuppressive Drugs, Blood Thinners by two to four hours. May counteract immunosuppressive effects

Does Spirulina interact with medications?

Documented interactions with immunosuppressive-medications, diabetes-medications, phenylketonuria-diet. Discuss these with a pharmacist before combining.

How do you know if you need Spirulina?

The marker is Complete blood count, protein status, or antioxidant markers, optimal range Improved nutritional markers and antioxidant status. Common deficiency signs: Not essential - but symptoms addressed by spirulina:, Protein deficiency and poor amino acid status, Low energy and fatigue, Poor immune function and frequent infections.

Taken for

59 Immunity

Vitamin D3 · Vitamin C (Ascorbic Acid) · Comprehensive Immune Support Complex

49 Liver & Detox

Turmeric · Vitamin C (Ascorbic Acid) · D-Mannose