Poris Mushroom, also known as Poria cocos or Fu Ling, is primarily used in Traditional Chinese Medicine (TCM). Historically, it has been valued for its diuretic, sedative, and tonic properties, and is commonly included in herbal formulas to strengthen the spleen, promote urination, and calm the mind. Its use for "free radical damage" (oxidative stress) is not a traditional indication per se, but as with many medicinal mushrooms, it has been ascribed general health-promoting and longevity benefits in TCM, which may indirectly encompass protection against age-related decline or cellular damage.

Modern research has identified that Poria cocos contains polysaccharides, triterpenoids, and other bioactive compounds with potential antioxidant properties. In vitro and animal studies have demonstrated some ability of Poria extracts to scavenge free radicals and reduce oxidative markers. However, this evidence is preliminary and limited; there are no robust clinical trials in humans directly supporting its use specifically for free radical damage or oxidative stress. Thus, its application for this purpose is primarily grounded in tradition, while scientific validation remains modest and largely preclinical.

In summary, Poria mushroom has a traditional reputation for supporting general health, which is sometimes extrapolated to antioxidant or anti-free radical effects, but rigorous scientific evidence to justify its use primarily for free radical damage is limited.