Supplementing with chlorella reduces oxidative stress and increases the activity of enzymatic and non-enzymatic antioxidants in rats[1] and increases antioxidant activity (by increasing levels of catalase and superoxide dismutase) in male smokers.[2] In humans, chlorella has notable antilipidemic, antihypertensive, and antihyperglycemic effects — it reduces total and LDL cholesterol, systolic and diastolic blood pressure, and blood glucose.[3][4]
The blood-glucose-lowering effects of chlorella may be due to its ability to improve insulin sensitivity and glucose uptake in the liver and skeletal muscles;[5][6] these effects may be more potent when chlorella is combined with exercise training.[7] Certain constituents of chlorella bind to digested dietary fat, increase the scavenging of LDL cholesterol, and reduce the absorption of sterols in the intestine, explaining chlorella’s cholesterol-lowering effects.[8][9][10]
Chlorella has exhibited detoxifying effects. It inhibited the intestinal absorption of dioxins (environmental contaminants and pollutants) in animal models and the absorption of heterocyclic amines in humans.[11] Chlorella also reduced mercury levels in the hair and blood of healthy adults.[12][13]