Beauty is not only in the face!A high “appearance level” may mean strong immune function, new research suggests

2022-05-31 0 By

As we all know, the love of beauty is universal.Good looks (a high level of physical attractiveness), or people with attractive faces, have long attracted widespread public interest.However, the objective criteria of beauty have always been controversial, and it seems impossible for humans to reach a consensus, hence “beauty is in the eye of the beholder”.Throughout history, human cultures have found certain physical features so attractive that others can be ignored.The answer to the question of why human perception systems find some physical features more attractive than others is undoubtedly complex, involving age, gender, culture and individual characteristics.Sexual selection theory, however, suggests that perceived attractiveness reflects preferences for traits related to a mate’s quality of life, including health and immune function.While this hypothesis is intuitively and theoretically appealing, solid evidence is lacking.February 16, 2022, Proceedings of the Royal Society B:In a new study in Biological Sciences, a team of researchers from Texas Christian University in the US has shown in the most extensive study to date that an individual’s facial attractiveness is linked to immune system function.The new study involved 159 young participants with an average age of 20, 79 of whom were women.All participants were tested in advance to ensure they had no history of chronic illness, were not depressed or otherwise mentally ill, were not obese, did not use steroids or anti-inflammatory drugs, did not exercise or drank alcohol in the two days prior to joining the study.The participants’ photos were rated for attractiveness in an online survey by 492 other participants (259 of whom were women) with an average age of 25.After taking photos of the participants, the researchers also conducted a series of tests on each participant to assess the state of their immune system, body inflammation levels and self-reported health.When analyzing the results, the researchers found that those who were rated as attractive had relatively healthy immune function, particularly when it came to bacterial immunity.Interestingly, there was no association between higher levels of inflammation and attractiveness among participants.This may suggest that facial attractiveness is a better proxy for a robust immune system than a sign of acute illness.In short, the main function of facial attractiveness may not be to avoid a sick partner, but to avoid a partner that might affect the health of your future offspring.The study also revealed some interesting gender differences.For example, men were more likely to be rated as attractive if their natural killer (NK) cells were powerful.These cells are essential for clearing the body of viral infections.For women, when the bacteria in their plasma grew slowly, they were rated more attractive.The bacteria are linked to levels of minerals, glucose and antibodies in the blood.Overall, the findings suggest that facial attractiveness may be linked to immune factors that can be passed on through genes, but that doesn’t mean there aren’t cultural factors that also influence an individual’s beauty, just that the weight of each is unclear.Given that mate preferences predate modern medicine, the link between attractiveness and health may have been overlooked in modern humans, the researchers said.This means that although attractiveness may have implied immune function and health in ancestral populations, its association with health may not be appreciated today because modern medicine can keep people with low immune function in relatively good health.In summary, one study is not enough to determine why human aesthetics exist and why facial attractiveness may serve some evolutionary purpose, if any.So further research is needed to replicate these results and explore what drives the link between physical attractiveness and immune function.The thesis links: https://royalsocietypublishing.org/doi/10.1098/rspb.2021.2476