Evidence Level
Chlorella research is growing but remains at an emerging evidence level, with most studies featuring small sample sizes and short durations. The strongest human evidence comes from Kwak et al. (2012), whose well-designed double-blind RCT demonstrated significant NK cell activation at 5g/day over 8 weeks. Ryu et al. (2014) provided credible lipid-lowering evidence in mildly hypercholesterolemic subjects. The heavy metal detoxification narrative is popular but less well-supported in humans — Uchikawa et al. (2010) showed dioxin-binding effects in animal models, and in vitro studies confirm metal-binding capacity of the cell wall, but controlled human trials specifically measuring heavy metal clearance are lacking. Chlorella Growth Factor (CGF), a nucleotide-peptide complex unique to chlorella, has shown immune and tissue repair properties in cell culture and animal studies. Hepatoprotective effects were demonstrated by Azocar & Diaz (2013) in hepatitis C patients, though the mechanism requires further elucidation. The broken cell wall form is essential for digestibility, as intact chlorella cell walls are indigestible by humans.