Skin colour predicts fruit and vegetable intake in young Caucasian men: A cross-sectional study

Abstract

Aim: Current dietary assessment methods are prone to subjective bias, highlighting the demand for an objective marker of fruit and vegetable (F/V) intake. Carotenoids from F/V consumption deposit in skin and adipose tissue, contributing to changes in skin colour. Results from research in females have highlighted positive associations between skin colour assessed by reflectance spectroscopy and F/V intake. The aim of this study was to determine the relationship between (i) F/V intake, (ii) carotenoid intake and skin colour in young Caucasian men. Methods: In this cross-sectional study reflectance spectroscopy was used to quantify skin colour in young Caucasian men. Skin colour was assessed at eight sun-exposed and unexposed body locations. A food frequency questionnaire was administered to assess F/V intake over the past month. Partial correlations were done to assess the associations between skin yellowness, F/V intake (grams) and carotenoid intake (milligrams), both with and without controlling for skin lightness. Results: Carotenoid intake was strongly associated with F/V intake (r = 0.8, p < 0.001). Skin yellowness was found to be strongly associated with both carotenoid (r = 0.599, p < 0.001) and F/V (r = 0.422, p = 0.02) intake. When skin colour was controlled for skin lightness and measured at the forehead, biceps, palm and foot sole, a stronger association was observed (carotenoid (r = 0.637, p < 0.001); F/V (r = 0.431, p = 0.02)). Conclusion: Skin colour is a viable biomarker of F/V intake in young Caucasian men. These findings contribute to the development of an objective marker of F/V intake, however more research is required before the method can be applied to practice.