Chapter 6: General discussion
6.5. Conclusions
In conclusion, this thesis has demonstrated that carotenoid colouration of human skin reflects aspects of health beyond diet. Evidence was presented which demonstrated that carotenoid colouration of skin reflected recent levels of psychological stress and recent instances of ill- health. Both of these effects were demonstrated with reference to variation in carotenoid colouration between individuals and changing levels of carotenoid colouration within individuals, suggesting that the effects are robust. Other health relevant variables were not found to relate to carotenoid colouration of skin and so further work is necessary to unpack the full relevance of carotenoid cues to health and the mechanisms sustaining relationships between carotenoid colouration and health variables which they reflect. Theoretically, this thesis supports the hypothesis that a preference for carotenoid colouration of skin would confer evolutionary benefits by providing cues to the bearer’s health and has practical implications in terms of monitoring health and motivating behaviour change.
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