Oral Pycnogenol® Intake Benefits the Skin in Urban Chinese Outdoor Workers: A Randomized, Placebo-Controlled, Double-Blind, and Crossover Intervention Study

<b><i>Background:</i></b> Oral supplementation with a standardized extract from the bark of the French pine (Pycnogenol®) has been reported to benefit the skin. It might thus represent an easy-to-use strategy to improve the skin health of individuals who are exposed to considerable environmental stress in large urban areas. <b><i>Objective:</i></b> We investigated if oral intake of Pycnogenol® can benefit the skin of Han Chinese working outdoors in Beijing, China. <b><i>Methods:</i></b> In a monocentre, double-blind, randomized, placebo-controlled, and crossover study, the effects of Pycnogenol® intake (2 × 50 mg/day for a total of 12 weeks) on a variety of skin physiological parameters was studied in Chinese subjects (<i>n</i> = 76), from spring to autumn, who were working outdoors in Beijing, China. <b><i>Results:</i></b> During the intervention period, study subjects were constantly exposed to increased levels of particulate matter (PM)_2.5 as well as seasonal changes in humidity and temperature. Despite this environmental stress, Pycnogenol® intake prevented (i) a decrease in the skin hydration, (ii) transepidermal water loss (TEWL), and (iii) skin darkening during the dry autumn season. In addition, Pycnogenol® intake improved (iv) viscoelastic skin properties such as gross elasticity and elastic recovery irrespective of the season. These beneficial effects were not observed if the same subjects were supplemented with placebo. <b><i>Conclusion:</i></b> Oral intake of Pycnogenol® benefits the skin in Han Chinese, who are working outdoors under considerable environmental stress.