Squalene is a naturally occurring triterpene found in high concentrations in shark liver oil and various plant sources, such as olives and amaranth. Its use to support or treat free radical damage is based on its role as a lipid-soluble antioxidant. Squalene can donate electrons to neutralize free radicals, thereby potentially reducing oxidative stress and protecting cellular components from damage.

Scientific studies, largely in vitro and in animal models, have demonstrated that squalene can scavenge reactive oxygen species (ROS) and may help protect lipids, proteins, and DNA from oxidative damage. For instance, a 2009 review in Phytotherapy Research highlighted squalene’s antioxidant properties, noting its ability to inhibit lipid peroxidation in cell membranes. Animal studies have suggested that dietary squalene may enhance antioxidant enzyme activity and decrease markers of oxidative stress.

However, human clinical evidence is limited. Most studies in humans focus on squalene’s role in cardiovascular health, skin health, or as a vaccine adjuvant, rather than its direct impact on free radical damage. There is some indirect support, as increased dietary squalene correlates with reduced oxidative markers in small-scale human studies, but robust, large-scale clinical trials are lacking.

In summary, while squalene possesses antioxidant properties in laboratory and animal studies, direct clinical evidence for its use in treating or preventing free radical damage in humans is limited. Its current use is supported more by preclinical research than by strong clinical validation.