Protective Effects of Oral Antioxidants on Skin and Eye Function

Pierfrancesco Morganti, PhD; Giuseppe Fabrizi, MD; Cesare Bruno

In This Article

Abstract and Introduction

Background: Antioxidants applied topically and/or taken systemically may play an important role in counteracting the oxidative injury to lipids and proteins on the skin and eye that are provoked by radical oxygen species.
Objective: The aim of the study was to control photoprotective activity of the skin and eye through the use of oral antioxidants in 50 smoker volunteers (10 cigarettes/d) aged between 25-36 years and affected by dry skin.
Methods: Oxidative stress was assessed by a randomized double-blind study, and the ROS-Meter System (Dermotech, Rome, Italy). Global visual function was determined by the use of different visual surveillance tests.
Results: A 40% decrease of oxidative stress in blood serum was verified, with a clear relationship between global visual function and the oral intake of an oxygenated carotenoid (lutein).
Conclusions: Carotenoids used as nutritional supplements seem to play an interesting photoprotective role for both skin and eyes, eventually increasing the activity of topical sunscreens.

The stratum corneum is exposed to a peroxidative environment that includes air pollutants and ultraviolet (UV) solar light.[1,2,3] Free radicals play an important role in skin aging and in the pathogenesis of several human diseases, such as coronary heart disease, cataractogenic process, and skin cancer.[4,5] To counteract this oxidative injury on the structure of lipids and proteins, human skin is equipped with a network of enzymatic and nonenzymatic antioxidant defense systems,[6] including tocopherols, ascorbate, polyphenols, and carotenoids.[7,8,9,10,11] These compounds, when administered either topically or orally, exert an antioxidant/protective effect on skin and skin cells.[12,13,14]

The object of this study was to evaluate the in vivo photoprotective activity performed by different kinds of nutritional supplements formulated with known antioxidant compounds, particularly in limiting radical oxygen species (ROS)-induced skin and eye damage such as skin drying and aging. To that end, oxidative stress on blood serum and global vision functions were assessed together with superficial skin lipids and skin hydration.