Objective:  Human skin colour is influenced by three pigments: haemoglobin, carotenoids, and melanin. Carotenoids are abundant in fruits and vegetables, and when consumed accumulate in all layers of the skin, predominantly imparting yellowness (b*). This study investigated the effect of the manipulation of carotenoid-based skin colour, relative to the skin colour conferred by melanin on the perceptions of health amongst a group of Australian adults.
Method:  Fifty-seven participants (n = 4 male; mean age 27.9 ± 7.5 years) completed three computer-based experiments on 50 trial faces. In the first two experiments, face image colour was manipulated along one or two independent single carotenoid or melanin axes on each trial to ‘make the face appear as healthy as possible’. In the third trial, face colour was manipulated on both the carotenoid and melanin axes simultaneously.
Results:  For the single axis, participants significantly increased melanin colouration and added carotenoid colouration to facial images that were initially low in skin yellowness (b*). When carotenoid and melanin axes were simultaneously manipulated, carotenoid colouration was raised (ΔE  = 3.15 ( SE  ±0.19)) and melanin colouration was lowered (ΔE  = −1.04 ( SE  ±0.1)).
Conclusions:  Young Australian adults perceive facial skin colouration, associated with both carotenoid intake from fruit and vegetables and melanin due to sun exposure as conveying the appearance of health in young adults. However, carotenoid colouration was more important to health perception.