Dosage
Trials commonly use 1.2 g to 8 g of chlorella per day, usually as tablets. Allow at least 8 weeks. Choose third-party tested products. Ask your healthcare provider before regular use if you take immune-suppressing or blood-thinning medicine.
Ingredient guide
Chlorella: Green Algae, Cholesterol, and Evidence
Chlorella is a green freshwater algae. A meta-analysis of 19 trials supports modest reductions in total cholesterol and LDL. It is rich in protein, B vitamins, and iron, and is sometimes used for heavy-metal binding, though the contamination risk of poor-quality chlorella is a real concern.
Moderate evidenceBenefits
- Meta-analysis of 19 RCTs showed reductions in total cholesterol of about 9 mg/dL.
- Studies also report small improvements in blood pressure and fasting glucose.
- Rich in protein, B vitamins (including B12), iron, and chlorophyll.
Evidence summary
What chlorella is
Chlorella is a single-celled green freshwater algae sold as a deep-green powder or tablet. It is roughly half protein by weight and contains B vitamins (including a form of B12 whose human availability is debated), iron, chlorophyll, and an outer cell wall component sometimes called chlorella growth factor.
What the human research shows
A meta-analysis of 19 randomised trials with 797 subjects found chlorella reduced total cholesterol by about 9 mg/dL and LDL by 8 mg/dL, plus small improvements in blood pressure and fasting glucose. Heavy-metal-binding claims rely largely on small studies in people with dental amalgam restorations. We grade the evidence as moderate for cardiometabolic markers.
Dosage & safety
Side effects
- The most common are gas, bloating, and loose stools at the start.
- Poor-quality chlorella may contain heavy metals or cyanotoxins.
- May make the stool green, which is harmless.
Interactions
- Chlorella may work against immune-suppressing medicine.
- Its vitamin K content may reduce the effect of warfarin.
Warnings
- Speak with a doctor or pharmacist before regular chlorella use if you take immune-suppressing medicine, since chlorella may stimulate the immune system.
- Choose products that are tested for heavy metals and cyanotoxins.
- Tell your provider you take it before any planned surgery, due to vitamin K content.
Products with this ingredient
Related ingredient guides
Citations
- Chlorella on cardiovascular risk factors: meta-analysis of RCTs pubmed.ncbi.nlm.nih.gov
- Chlorella benefits, dosage, and side effects (Examine) examine.com
Frequently asked questions
Does chlorella lower cholesterol?
A meta-analysis supports a modest reduction in total and LDL cholesterol. It is a real but small effect over weeks.
Is chlorella safe?
Quality matters most. Poor-quality chlorella can contain heavy metals. Choose tested, reputable products and start with a low dose.