Anti-Inflammatory Activity of Colloidal Oat (Avena sativa)

Oat (Avena sativa) has been cultivated since the Bronze Age, and has been used for topical applications for centuries. Colloidal oatmeal is the finely ground whole oat kernel, which is an active natural ingredient covered by the FDA OTC Skin Protectant monograph in the US. As a food, the constituents of oat have been well studied. Oats groats are a rich source of unsaturated omega-3 linoleic and omega-6 linolenic acids as triglycerides, mixed tocopherols and tocotrienols, β-glucan, and phenolic compounds. Oats also contain avenacins, saponins that form stable emulsions. Despite the known phytochemistry and centuries of clinical evidence of skin benefits, many of the mechanisms of action that make colloidal oats beneficial to the skin remain unclear. We found that extracts of colloidal oat significantly attenuate the UV-induced production of reactive oxygen species from primary human keratinocytes. Furthermore, our studies determined that extracts of colloidal oat reduced the levels of the pro-inflammatory mediator, IL-8, in a UV-induced inflammation model of keratinocytes. Taken together, these results demonstrate that colloidal oats have direct anti-oxidant and anti-inflammatory activity which may provide the therapeutic effect for dermatological conditions.