Until now, it was thought that men preferred these figures because it told them that a woman was healthy and fertile, but now scientists are alleging that it gives away so much more information than that. “For the past 30 years the explanation for male preferences that has generally been accepted is that they look for signs of health and fertility, but we have shown that the very small waist sizes and low BMIs linked with attractiveness in well-nourished women do not indicate better health or fertility,” Lassek tells PsyPost.