Carotenoids could serve as marker substances of the antioxidant status of the human skin. In the present study, an optical skin scanner was used to analyse the carotenoid concentration obtained from 4 volunteers over a period of 13 days. The measurements were taken daily at different time points. In addition, the volunteers were asked to keep track of their daily nutritional behaviour and stress situations in a diary. It was found that the carotenoid values reflect clearly the nutritional behaviour and stress situations of the volunteers. While a steady, increased intake of fruit and vegetables resulted in a gradual increase in the dermal carotenoid values for several days, stressful situations entailed an immediate decline in these values. Although the impact of healthy nutrition on the antioxidant protection system is generally known and notwithstanding the small number of cases, the present study clearly demonstrates that the avoidance and/or reduction of stress is similarly important in order not to counteract or nullify the results achieved by healthy nutrition.