Dietary Antioxidant Capacity and Skin Photoaging: A 15-Year Longitudinal Study

The long-term effect of diet on skin aging is largely unknown, but evidence suggests that the antioxidants from foods may mitigate the main component of skin aging caused by sun exposure. We assessed the association between the total antioxidant capacity of foods people eat and the photoaging of their skin. In a community-based, prospective study among 777 Australian adults aged <55 years at baseline, we estimated the total dietary antioxidant capacity of participants' diets in 1992, 1994, and 1996 and graded photoaging severity using microtopography in 1992, 1996, and 2007. We used ordinal logistic regression and applied generalized estimating equations to estimate change in the degree of photoaging associated with increasing total antioxidant capacity compared with the group with the lowest antioxidant capacity, separately in younger (≤45 years) and older (>45 years) adults. In the 15-year study period, the overall prevalence of severe skin photoaging increased from 42% at baseline to 88%. Adults aged >45 years who consumed foods with high antioxidant capacity experienced approximately 10% less photoaging over 15 years than those who ate foods with low antioxidant capacity. No association was found among adults aged ≤45 years. Foods rich in antioxidants as measured by antioxidant capacity may retard skin aging among healthy men and women aged >45 years.