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📰Read the full Chlorella evidence review on GMJ News →Complete clinical article, references and updates on news.gmj.ge. This page is the structured safety summary.⚠ MUST be broken cell wall for bioavailability [1]
⚠ Detox claims are in vitro — human evidence minimal [2]
⚠ Warfarin patient — high vitamin K content [1]
⚠ Less studied than spirulina [1]
ℹ️ Not obtained from food. Not applicable — this is not obtained from food in meaningful amounts; supplementation is the practical route.
🔬 Lab interpreter
Recommended test
INR (if on warfarin)
INR (if on warfarin)
Reference range / target
Therapeutic range
Therapeutic range
Vitamin K content [1].
Full lab monitoring ↓⚕ For professionals — confirm ranges against your local laboratory.
Clinical verdict
Chlorella is nutrient-dense (50–60% protein, high chlorophyll) but requires broken cell wall for absorption. Detox claims (heavy metal binding) are in vitro only — human evidence is minimal. Less clinical data than spirulina. Vitamin K content — warfarin interaction. Always buy 'broken/cracked cell wall' products [1] [2].
1 How much do I need?
👤 Adults: Specific dosage data under clinical review
👴 Elderly: Specific dosage data under clinical review
🤰 Pregnancy: See guidance
Limited data. Contamination risk. Use certified products [1].
👦 Pediatric: See guidance
Limited data [1].
🏃 Athletes: Standard dose
⚖️ Obesity: Standard dose
Fat-soluble compounds may require dose adjustment in obesity.
🩺 Renal: Consult specialist
Dose adjustment may be needed in renal impairment.
🌱 Vegan: Standard dose
How to take
🍽 Timing: Any time [1].
💊 With food: Mix in smoothies [1].
🚫 Avoid: Warfarin without INR monitoring. Immunosuppressants [1].
2 Which form?
| Form | Bioavailability | Vegan | Cost |
|---|---|---|---|
| ['Broken/cracked cell wall chlorella', 'preferred', 'Cell wall processing required for nutrient absorption. Tablets or powder [1].'] | Standard | Check label | |
| ['Chlorella powder', 'common', 'Green powder. Strong taste. 3–10 g/day [1].'] | Standard | Check label |
3 Common questions
Does chlorella detox heavy metals? ▼
It binds metals in laboratory settings. Whether oral chlorella meaningfully removes heavy metals from human tissues is NOT proven [2]. The 'detox' marketing is far ahead of the science.
Broken cell wall — does it matter? ▼
YES — chlorella has a tough cellulose cell wall. Without cracking/breaking, nutrients are largely unabsorbed [1]. Always buy 'broken cell wall' products.
Chlorella vs spirulina? ▼
Chlorella: true alga, higher chlorophyll, broken cell wall needed. Spirulina: cyanobacterium, higher protein and phycocyanin, no cell wall issue. Both are nutritious. Spirulina has more clinical data [1].
4 Clinical evidence
Strong
Nutrient density: 50–60% protein, high chlorophyll, vitamins, minerals — well-characterized [1]. Cell wall barrier to absorption without processing — established [1]. HIGH
Moderate
Lipid reduction: some small trials show modest cholesterol and TG reduction [2]. Heavy metal binding in vitro: chlorella binds cadmium, lead, mercury in laboratory studies [2]. Immune function: increased NK cell activity and sIgA in small trials [2]. Blood pressure: modest reduction in some studies [2]. MODERATE
Insufficient
5 Safety, toxicity & adverse events
Relative
⚠ Concurrent warfarin — vitamin K content may reduce INR
⚠ Autoimmune diseases — immunostimulatory effects
⚠ Iodine sensitivity — chlorella may contain iodine
⚠ Heavy metal contamination risk — source from certified producers
🚩 Red flags
● Warfarin patient — vitamin K [1]
● Product not 'broken cell wall' — nutrients unabsorbed [1]
6 Interactions
Drug interactions
Warfarin Moderate
Mechanism: High vitamin K content. [1]
Effect: Reduced INR. [1]
Action: Consistent intake; monitor INR [1].
Supplement synergies
Spirulina · 1–5 g spirulina
Complementary algae/cyanobacteria profiles [1].
Complementary algae/cyanobacteria profiles [1].
7 Regulatory
Japan: Major consumer market. Long history of use [1].
United States (FDA): GRAS. Dietary supplement [1].
8 US supplement products
269
on-market products containing Chlorella (NIH DSLD)
Brands carrying Chlorella (112)
Click a brand to see its Chlorella products.
9 Frequently paired with
10 Cite this page
Vancouver: Pkhakadze G. Chlorella — safety profile [Internet]. Tbilisi: PHIG; 2026 [cited 2026 Aug 19]. Available from: https://supplement.ge/ingredients/chlorella/
APA 7th: Pkhakadze, G. (2026). Chlorella — Safety profile. Public Health Institute of Georgia. https://supplement.ge/ingredients/chlorella/
📋 Editorial information
Author: Prof. G. Pkhakadze, MD, MPH, PhD
Institution: Public Health Institute of Georgia (PHIG)
Affiliation: David Tvildiani Medical University (DTMU)
First published: January 2026
Last reviewed: 2026-05-29
Next review: February 2027
References: 2 cited sources
COI: SupplementIndex receives no funding from supplement manufacturers. All content independently authored by PHIG.
Process: Systematic literature review
📄 License & reuse
Published under Creative Commons Attribution 4.0 International (CC BY 4.0). You may share and adapt for any purpose with attribution.
Pkhakadze G. "Chlorella — Safety Profile." SupplementIndex, PHIG, 2026. https://supplement.ge/ingredients/chlorella/ CC BY 4.0.
GP
Prof. G. Pkhakadze, MD, MPH, PhD
Professor of Public Health · Head of Department, DTMU
Editor-in-Chief, Georgian Medical Journal (ISSN 3088-4322)
Chair, Public Health Institute of Georgia · UEMS Public Health Section
Educational and public health purposes. CC BY 4.0. Consult your healthcare provider before starting any supplement. Corrections: info@accreditation.ge. Publisher: PHIG