Written by the Plenthera team (orthomolecularly trained). Scientifically reviewed in April 2026. Last updated: April 30, 2026.
Chlorella is a single-celled green freshwater alga with the highest chlorophyll content of all known foods. It is often mentioned in the same breath as spirulina, but the two are fundamentally different: chlorella is a true alga, with a hard cell wall that must be broken for absorption. At Plenthera, you will only find broken cell wall chlorella — powder and tablets — from controlled production in Taiwan and Germany.
Chlorella vs. Spirulina — what suits you?
| Aspect | Chlorella | Spirulina |
|---|---|---|
| Type | True green alga | Cyanobacterium |
| Chlorophyll | Highest of all foods | Significantly less |
| B12 | Biologically active | Pseudo-B12 (ineffective) |
| Cell wall | Hard — must be broken | No cell wall |
| Protein content | 50-60% | 55-70% |
| Best for | Chlorophyll theme, B12, detox research | Protein, energy, phycocyanin |
What is chlorella?
Chlorella (Chlorella vulgaris and sorokiniana) is a single-celled green freshwater alga. It contains 50-60% protein, the highest chlorophyll content of all foods, and biologically active vitamin B12 — unique among plant-based sources.
Chlorella was first described by the Dutch microbiologist Martinus Beijerinck in 1890. The name comes from the Greek "chloros" (green) — the cell is packed with chlorophyll, the pigment that gives plants and algae their green color. What makes chlorella remarkable is its multiplication speed: under ideal conditions, a chlorella cell quadruples every 17-24 hours, a characteristic that makes it attractive for commercial production.
In the 1950s and 60s, chlorella was considered a solution to global food shortages — high protein yield per hectare, fast-growing, and no fertile soil needed. That ambition was never fully realized, but in Japan, Korea, and Taiwan, chlorella has since remained a popular dietary supplement. Only in the 1990s did chlorella become commercially available in Europe and the United States.
A crucial aspect of chlorella is its cell wall. Unlike spirulina (a cyanobacterium without a cell wall), chlorella has a hard, cellulose-rich cell wall that the human gastrointestinal system cannot break down. Therefore, "broken cell wall" (BCW) — mechanically or enzymatically broken — is an absolute prerequisite for effective supplementation. At Plenthera, we exclusively supply BCW-chlorella. Also check our spirulina category for a direct comparison and combined products.
Science, CGF, and EFSA status
Chlorella is widely studied in relation to heavy metal binding (due to its chlorophyll-rich matrix), immunomodulation, and general nutritional support. A specific component that receives attention is CGF (Chlorella Growth Factor) — a mixture of peptides, polysaccharides, and nucleic acids that arises during the rapid cell division of chlorella.
Clinical research in humans is limited in scope and quality. For chlorella, several small-scale studies have been conducted on cholesterol, immune function, and antioxidant activity, with predominantly positive but methodologically limited results.
Important: there are NO health claims specifically for chlorella recognized by EFSA. Therefore, we do not make literal claims about its efficacy. Chlorella is a dietary supplement, not a medicine. When using medication (especially blood thinners and immunosuppressants): consult a doctor beforehand.
Broken cell wall — why this is crucial
Chlorella's hard cell wall consists of cellulose and sporopollenin — substances that the human digestive system cannot break down. A chlorella supplement without a broken cell wall largely passes through the gastrointestinal tract undigested; the nutrients remain inaccessible within the cell.
Three methods to break the cell wall: mechanical (pressure processing, sonication), thermal (heat-pressure cycles), or enzymatic (specific enzymes). Mechanical processing under cold conditions best preserves the heat-sensitive components.
At Plenthera, we work exclusively with broken cell wall (BCW) chlorella. Non-BCW chlorella is cheaper, but worthless for effective supplementation.
The chlorella forms at Plenthera
Chlorella tablets (BCW)
Pressed tablets without binder — 100% pure chlorella with broken cell wall. Practical for on-the-go and for those who don't want to mix the taste into a drink.
Chlorella powder (BCW)
Finely ground chlorella with broken cell wall — deep green in color. Can be mixed into smoothies or juices. Flavor profile: green-earthy, slightly sea-like.
Chlorella + spirulina combination
Both microalgae combined for a broader profile — chlorella for chlorophyll and cell wall-binding properties, spirulina for extra protein and pigment proteins.
How do you use chlorella?
Simple basic approach for chlorella:
- Determine your goal: daily supplement (3-5 g), B12 supplement (4-6 g) or more intensive use (5-10 g).
- Choose the form: tablets for on the go, powder for smoothies, combination for a broad profile.
- Start with a low dosage (1-2 g) and gradually build up to allow the digestive system to adjust.
- Mix the powder into a smoothie or juice with a strong flavor for masking.
- Can be taken with or without food; with a sensitive stomach, preferably with a meal.
- Many users divide the dosage over two times — morning and afternoon.
- When using medication (blood thinners, immunosuppressants): consult a doctor beforehand, in accordance with the advice of the NVWA.
Myths and misunderstandings about chlorella
Myth 1: "All chlorella works — the cell wall doesn't matter."
Incorrect and commercially relevant. Chlorella without a broken cell wall largely passes through the digestive system undigested. A non-BCW product is essentially wasted money. Always ask for broken cell wall (BCW) or cracked cell wall (CCW).
Myth 2: "Chlorella detoxifies heavy metals from the body."
In laboratory tests, chlorella binds heavy metals due to its chlorophyll-rich matrix. Whether this translates clinically to significant heavy metal removal in humans has not been conclusively proven scientifically. EFSA has not recognized any claims for this.
Myth 3: "Chlorella is a complete substitute for green vegetables."
Chlorella is a supplement, not a substitute. 5 grams of chlorella contains about 3 grams of protein and a touch of many micronutrients — but lacks the fiber, phytochemicals, and bulk of real vegetables.
Myth 4: "The more chlorella, the faster it works."
Starting with high doses can cause nausea, stomach upset, or diarrhea. Gradually building up is always better than acutely high dosing.
Combining chlorella with other supplements
Chlorella is often combined with other supplements for a broader nutritional profile. Popular combinations:
- Spirulina: complementary microalgae — both together provide a broader profile.
- Vitamin C: supports iron absorption from chlorella and acts as a synergistic antioxidant.
- Vitamin B12: for those who want certainty about B12 status (chlorella does provide B12, but for clinical deficiency, a specific supplement is more reliable).
- Maca: superfood combination for energy.
- Moringa: complementary green powder with other nutrients.
Frequently Asked Questions
What is chlorella?
A single-celled green freshwater alga with the highest chlorophyll content of all foods. Contains 50-60% protein and biologically active B12.
How does chlorella work?
Chlorella provides protein, chlorophyll, B12, iron, and CGF. Research focuses on heavy metal binding and immunomodulation. EFSA claims do not exist.
What is broken cell wall chlorella?
Chlorella has a hard cell wall that humans cannot break down. Broken cell wall (BCW) chlorella has it mechanically or enzymatically broken — essential for absorption.
How much chlorella per day?
3-5 grams as a general daily portion. For more intensive use, up to 10 grams per day.
When to take chlorella?
Timing is flexible. With a sensitive stomach: with a meal. Many users divide the dose over two times.
What is the difference between chlorella and spirulina?
Chlorella: green alga with hard cell wall, high chlorophyll, true B12. Spirulina: cyanobacterium without cell wall, blue phycocyanin, pseudo-B12.
Does chlorella help with detox?
No detox claims recognized by EFSA. In the laboratory, chlorella binds heavy metals, but clinical translation has not been conclusively proven.
Does chlorella contain real B12?
Yes — chlorella contains biologically active B12 (cobalamin), unique among plant sources. For certainty for vegans, a dedicated B12 supplement is still recommended.
Does chlorella have side effects?
Generally well tolerated. Some report mild stomach upset or nausea with rapid build-up. Consult a doctor beforehand if using medication.
How do I recognize quality chlorella?
Broken cell wall declaration, traceable origin (Taiwan, Korea, Germany), heavy metal testing, organic certification.
Sources
- Merchant RE. & Andre CA., "A review of recent clinical trials of the nutritional supplement Chlorella pyrenoidosa", Altern Ther Health Med (2001).
- Bito T. et al., "Potential of Chlorella as a Dietary Supplement to Promote Human Health", Nutrients (2020).
- Panahi Y. et al., "Chlorella vulgaris: A multifunctional dietary supplement with diverse medicinal properties", Curr Pharm Des (2016).
- EFSA Novel Food Catalogue — Chlorella status.
Disclaimer: This text is for informational purposes only and does not replace medical advice. Chlorella is a dietary supplement, not a medicine. If in doubt or when using medication, we recommend consulting a doctor or orthomolecular therapist first.