Plant-Based Foods for Skin Health: A Narrative Review
“Collectively, the evidence to date suggests a promising future for plant-based dietary interventions that promote skin barrier health and function.”https://www.sciencedirect.com/science/article/pii/S2212267221014337
In conclusion, clinical studies in the field of nutrition and skin research support growing evidence to help dietitians make targeted dietary recommendations. More investigations on whole foods and beverages, as well as those fortified with plant-based extracts, are needed to extend current findings.
From the study:
Skin, the largest organ in the human body, acts as a barrier to protect internal organs and cells from external elements. It also helps regulate body temperature, mediates sensations of touch, and produces vitamin D, a key regulator of bone, immune, and vascular health.3 Both intrinsic and extrinsic factors affect skin health and aging.4 An individual’s genetic background influences intrinsic factors such as skin pigmentation, skin thickness, microvasculature structure, and sex hormones.4 Extrinsic factors such as smoking, diet, sleep, exercise, chronic diseases, and environmental factors including temperature, pollution, humidity, and UV radiation (UVR) can increase inflammation and oxidative stress that accelerate skin aging.4, 5, 6 Indeed, repeated UVR exposure can increase pro-inflammatory cytokines that contribute to the development of wrinkles and adverse pigmentation of the skin.7 Moreover, age- or obesity-related induction of protein glycation and inflammation can increase skin rigidity and impair skin repair.8
Suboptimal nutrition can adversely affect skin health, as evidenced in studies of micronutrient deficiencies. For example, deficiencies of vitamin A and vitamin C (VitC) can lead to thickening of the skin.9 Poor wound healing has been observed with deficiencies of VitC and essential fatty acids,9, 10, 11 and petechiae can be a result of vitamin E and vitamin K deficiencies.9 Inadequate intakes of riboflavin, niacin, pyridoxine, biotin, zinc, and essential fatty acids can lead to various forms of dermatitis.9,12 Classic studies on pellagra13 and acrodermatitis enteropathica14 identified niacin and zinc deficiencies, respectively, as causative factors. Although the data on micronutrient deficiencies are extensive, data on how specific foods or diets can influence skin health in well-nourished populations are limited.
Epidemiological studies suggest that abundant dietary intakes of specific plant-based foods are key in the maintenance of skin barrier health and function. A robust intake of vegetables, olive oil, and legumes was correlated with lower actinic skin damage caused by long-term UVR exposure among 2000 people aged 70 and older in Australia, Greece, China, Japan, and Sweden.1 Better adherence to the Dutch Healthy Diet Index guidelines that promote a diet rich in fruits and include yogurt, milk, and vegetables was significantly associated with fewer wrinkles in women.2 Among Japanese women, a significant inverse association has been observed between wrinkling and green and yellow vegetable intake.15 In contrast, diets consisting mainly of meat, refined grains, snacks, soft drinks, coffee, and alcoholic beverages were associated with more wrinkling in women.2
Plant-based foods are rich in polyphenols, carotenoids, and select vitamins typically not found in appreciable amounts in other food categories. However, each food has a unique nutrient profile that provides an array of bioactive compounds that either alone or synergistically may afford protection for the skin.
Given this information, we conducted a preliminary survey of recent literature on the potential effects of plant foods on skin barrier health and function. A majority of the trials discussed used study designs of dietary components and foods individually, at times, above dietary recommendations. However, the goal of this review is to spark interest in this field, as well as provide an overview of the available data for both the public and nutrition professionals who have an interest in the role of diet for the maintenance of skin barrier health and function. This review aims to provide more specificity in terms of the fruits and vegetables that may improve skin barrier function and meet the recommendations of the 2020-2025 Dietary Guidelines for Americans (DGAs).