People look for candidates with a healthy complexion when choosing a leader, but don't favor the most intelligent-looking candidates except for positions that require negotiation between groups or exploration of new markets. These results are published in the open-access journal Frontiers in Human Neuroscience.

Brian Spisak from the VU University Amsterdam and colleagues studied people's implicit preferences for traits of leaders, such as health, intelligence, and attractiveness, and how they look for information about these qualities in the physical appearance of others.

The researchers focused on facial traits because these provide a wealth of information about individuals. For example, in women as well as men, caring and cooperative personalities are statistically more likely to have a more "feminine" face, due to higher estrogen levels, while aggressive risk-takers tend to have higher testosterone levels and a more "masculine" face.

They asked 148 women and men to imagine that they were selecting a new CEO for a company and to repeatedly pick between two photos of male faces. For each choice, the participants were given a job description that specified the CEO's main challenge. This was either to drive aggressive competition, renegotiate a key partnership with another company, lead the company's shift into a new market, or oversee the stable, sustained exploitation of non-renewable energy.

In each choice, both photos were of the same man, whose face had been digitally transformed. His face had been made to look more or less intelligent while his complexion was changed to look more or less healthy.

A stronger general preference for health than intelligence was found. The participants chose more healthy-looking faces over less healthy-looking faces in 69% of trials, and this preference was equally strong irrespective of the future CEO's main challenge. More intelligent-looking faces were only preferred over less intelligent-looking faces for the two challenges that would require the most diplomacy and inventiveness: renegotiating the partnership and exploring the new market.

"Here we show that it always pays for aspiring leaders to look healthy, which explains why politicians and executives often put great effort, time, and money in their appearance. If you want to be chosen for a leadership position, looking intelligent is an optional extra under context-specific situations whereas the appearance of health appears to be important in a more context-general way across a variety of situations," says Spisak, lead author of the paper and Assistant Professor at the Department of Management and Organization of VU University Amsterdam.