Amentoflavone is a naturally occurring biflavonoid found in several plants, such as Selaginella tamariscina and Ginkgo biloba. Its use for supporting or treating free radical damage is primarily justified by emerging scientific evidence rather than traditional medicine. Several in vitro and animal studies have demonstrated that amentoflavone possesses antioxidant properties. These properties are attributed to its ability to scavenge free radicals and modulate oxidative stress-related pathways, such as the inhibition of reactive oxygen species (ROS) production and enhancement of endogenous antioxidant enzymes (e.g., superoxide dismutase, catalase).

For example, research published in journals like Bioorganic & Medicinal Chemistry and Phytomedicine has shown that amentoflavone can decrease lipid peroxidation and protect cells from oxidative damage in various experimental models. However, the majority of available data comes from preclinical studies, and there is a lack of well-designed clinical trials assessing its efficacy in humans for the prevention or treatment of free radical-related damage or diseases. Thus, while the compound shows promise as an antioxidant, the evidence supporting its use in humans remains limited and preliminary.

In summary, amentoflavone's use for free radical damage is backed by some scientific studies, but the strength of evidence is moderate at best due to the lack of robust clinical research.