A new study says that women prefer men with yellower and redder skin tones, an indication of good health and a crucial factor in choosing a partner.

People who eat a diet rich in fruits and vegetables tend to be yellower and those who are physically fit have redder blood and skin, because they are more oxygenated. These factors are common irrespective of the race of a person.

Those who are generally considered unattractive have pallid skin with lesions, which could be due to a weak immune system.

"What we found is—to our surprise—when you measure masculinity, it doesn't bear any relation to attractiveness at all," said study co-author Ian Penton-Voak, an experimental psychologist at the University of Bristol in the U.K.

The researchers took 20 photos of Caucasian men in northern England with an average age of 27 and showed them to 21-Caucasian women with an average age of 19. Each of the women was asked to judge the attractive men in the picture and they preferred men with yellower and redder skin tones. Interestingly the women were not interested in the men with masculinized faces that were digitally altered over the original photos.

"Still, the new study doesn't rule out the chance that cultural differences influence which physical traits women find attractive, said Laura Dane, an evolutionary psychologist at Douglas College in British Columbia, Canada.

"Physical attractiveness is not the only thing that women use to choose" a partner, said Dane.