Using specialist computer software, a total of 54 Caucasian participants of both sexes were asked to manipulate the skin colour of male and female Caucasian faces to make them look as healthy as possible. They chose to increase the rosiness, yellowness and brightness of the skin.
‘Most previous work on faces has focused on the shape of the face or the texture of the skin, but one of the most variable characteristics of the face is skin colour’, said Dr Ian Stephen who was previously at St Andrews but is now in the Department of Experimental Psychology at the University.
‘We knew from our previous work that people who have more blood and more oxygen colour in their skin looked healthy, and so we decided to see what other colours affect health perceptions. This has given us some clues as to what other skin pigments may relate to a healthy appearance.’
Skin that is slightly flushed with blood and full of oxygen suggests a strong heart and lungs, supporting the study’s findings that rosier skin appeared healthy. Smokers and people with diabetes or heart disease have fewer blood vessels in their skin, and so skin would appear less rosy.
The preference for more golden or ‘yellow-toned’ skin as healthier might be explained by the ‘carotenoid pigments’ that we get from the fruit and vegetables in our diet.
These plant pigments are powerful antioxidants that soak up dangerous compounds produced when the body combats disease. They are also important for our immune and reproductive systems and may help prevent cancer.
They are the same dietary pigments that brightly coloured birds and fish use to show off their healthiness and attract mates, and the researchers think that similar biological mechanisms may be at work in humans.
‘In the West we often think that sun tanning is the best way to improve the colour of your skin’, said Ian Stephen, ‘but our research suggests that living a healthy lifestyle with a good diet might actually be better.’
Melanin, the pigment that causes the tan colour when skin is exposed to the sun makes the skin darker and more yellow, but participants in the study chose to make skin lighter and more yellow to make it look healthier.
‘This discovery is very exciting and has given us a promising lead into cues to health’, said Professor David Perrett, head of the Perception Lab at the University of St Andrews, where the research took place.
‘What we eat and not just how much we eat appears to be important for a healthy appearance. The only natural way in which we can make our skin lighter and more yellow is to eat a more healthy diet high in fruit and vegetables.’
The work will be published in the December issue of the International Journal of Primatology and has been funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and Unilever Research, and published with support from the Economic and Social Research Council (ESRC) and the British Academy.
- The paper: Stephen, I.D. et al (2009) ‘Facial skin coloration affects perceived health of human faces’, International Journal of Primatology, DOI: 10.1007/s10764-009-9380-z.
- A pdf of the original article and images are available from the St Andrews press office. Contact Philippa Dunn, Assistant Press Officer on 01334 462530/462529, mobile: 07730 415015 or email firstname.lastname@example.org. The images can also be downloaded here.
- Ian Stephen is available for comment or interview and can be contacted on 0117 954 6847 or email email@example.com.
- Dave Perrett is available for comment or interview on firstname.lastname@example.org.
- The Economic and Social Research Council (ESRC) is the UK’s largest organisation for funding research on economic and social issues. It supports independent, high quality research which has an impact on business, the public sector and the third sector. The ESRC’s planned total expenditure in 2009/10 is £204 million. At any one time the ESRC supports over 4,000 researchers and postgraduate students in academic institutions and independent research institutes.
- The Biotechnology and Biological Sciences Research Council (BBSRC) is the UK funding agency for research in the life sciences. Sponsored by Government, BBSRC annually invests around £450 million in a wide range of research that makes a significant contribution to the quality of life for UK citizens and supports a number of important industrial stakeholders including the agriculture, food, chemical, healthcare and pharmaceutical sectors. BBSRC carries out its mission by funding internationally competitive research, providing training in the biosciences, fostering opportunities for knowledge transfer and innovation and promoting interaction with the public and other stakeholders on issues of scientific interest in universities, centres and institutes. The Babraham Institute, Institute for Animal Health, Institute of Food Research, John Innes Centre and Rothamsted Research are Institutes of BBSRC. The Institutes conduct long-term, mission-oriented research using specialist facilities. They have strong interactions with industry, Government departments and other end-users of their research.