Photoaging is a leading concern for patients seeking dermatologic care. The long-term effects of ultraviolet (UV) radiation include rhytides, dyschromia, lentigines, actinic damage, and malignant neoplasms. As public knowledge has increased regarding the link between sun exposure and photoaging, patients have become interested in both preventing and treating the adverse effects of UV radiation.
Today's dermatology patient has often sought online medical advice prior to their consultation, and may have a strong desire to utilize only organic and natural ingredients. What is meant by the terms "organic" and "natural"? Organic is a term designated by the United States Department of Agriculture (USDA), but it is not regulated by the US Food and Drug Administration (FDA). To complicate matters, the FDA has no definition for the term natural. Despite a lack of standardized guidelines across organizations to set parameters for organic labeling, organic products have multiplied and some organic products may be equally, if not more, modified than conventional products. In addition, natural products are not necessarily organic. For the purposes of this article, natural products will refer to ingredients derived from nature, mainly plants, which are later improved upon in the laboratory. This improvement is what allows the natural ingredient to perform its intended effect on the skin: by increasing its ability to penetrate into the epidermis, by allowing it to remain on the skin without denaturing, and by ensuring that it plays an active role in vivo.
Natural products have gained popularity in recent years due to the presence of antioxidants, and increased use of this term in the popular media. Free radicals are highly reactive oxygen species that can cause significant damage to lipids, proteins, carbohydrates and DNA. They accumulate during daily activities such as respiration and exercise, but can be exacerbated by inflammation, drugs, and the environment, enhancing the degree of oxidative damage.1 The environmental factors that can drastically increase free radical production include UV radiation, smoking, and stress. Free radical production can overwhelm endogenous antioxidant activity, leading to oxidative stress and contributing to the aging process. Replenishment of endogenous antioxidant stores with natural products containing a wealth of antioxidants is protective against oxidative damage.
Natural products that may play a role in preventing and treating photoaging include mushrooms, feverfew, green tea, licorice, olive oil, soy, and coffee berry. In this review, we will discuss clinical studies to support this claim, with basic science studies included when there is a paucity of clinical data. It is important to remember that while basic science data may hint at the efficacy of a product or its mechanism of action, this will not necessarily translate to in vivo effect or mechanism. Although it is encouraging that the clinical studies discussed show a benefit when used in human subjects, the studies are limited and the data is not powered to allow for definitive recommendations. As an additional caveat, some mentioned studies discuss the use of extracts, or ingredients obtained from a particular substance. Extracts do not always contain all of the active ingredients of the original product and can vary from one another based on the method of removal. This variation makes it difficult to generalize data from individual studies, especially when the method of extraction, ingredients within the extract, and additive substances are not defined.
Mushrooms have been utilized for medicinal purposes for many years. They contain potent antioxidants, including phenolic acids, flavonoids, tocopherols, ascorbic acid, and carotenoids.1 Mushroom polysaccharides prevent oncogenesis, exhibit antitumor activity, and prevent tumor metastasis via activation of the host immune response.2 Mushroom species vary in composition, and some mushrooms may exhibit minimal antioxidant properties. In addition, the efficacy of mushrooms can be affected by variations in preparation.