Curcuminoids, the active polyphenolic compounds in turmeric (Curcuma longa), have been extensively researched for their antioxidant properties and potential to combat free radical damage. Scientific studies have demonstrated that curcuminoids, particularly curcumin, can act as free radical scavengers and enhance the activity of endogenous antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. These effects have been observed in in vitro experiments, animal models, and some human clinical trials.

A number of preclinical studies have shown that curcuminoids protect cells from oxidative stress-induced damage by neutralizing reactive oxygen species (ROS) and reducing lipid peroxidation. Systematic reviews and meta-analyses of clinical trials indicate that curcumin supplementation can lower biomarkers of oxidative stress in humans, such as malondialdehyde (MDA), and increase antioxidant capacity.

However, despite promising results, factors such as bioavailability and variability in study design mean that the evidence is not yet considered definitive for all clinical contexts. Nevertheless, the scientific rationale for using curcuminoids to support the body's defense against free radical damage is strong, and ongoing research continues to explore optimal formulations and clinical applications.