Phycocyanins are pigment-protein complexes found in cyanobacteria (such as spirulina) and certain algae. Their use to support or mitigate free radical damage is justified by scientific research rather than traditional medicine. Multiple in vitro and animal studies have demonstrated that phycocyanins possess significant antioxidant properties, primarily due to their ability to scavenge free radicals and reduce oxidative stress. The antioxidant activity is often attributed to their chromophore, phycocyanobilin, which has a chemical structure similar to bilirubin, a known endogenous antioxidant.

Scientific studies have shown that phycocyanins can inhibit lipid peroxidation and protect cells from oxidative stress-induced damage. For example, research published in peer-reviewed journals has indicated that phycocyanins reduce markers of oxidative stress in animal models and provide protection against oxidative damage in various tissues. However, while the evidence from laboratory and animal studies is promising, there are comparatively fewer high-quality human clinical trials directly evaluating phycocyanins for the prevention or treatment of free radical damage in humans. Thus, the scientific evidence, while supportive and mechanistically plausible, is not yet conclusive.

In summary, phycocyanins are used to support free radical damage based on scientific, not traditional, evidence. The overall strength of evidence is moderate (rated 3/5), largely due to a solid foundation of preclinical research, with some emerging—but limited—clinical data.