Chapman University has published research on how many sex partners people have relative to their height and body mass. The study focused on 60,058 heterosexual men and women asking each to indicate their height, weight, and how many sex partners they have had. The median number of "sex partners" reported for both men and women ages 30 to 44 was eight partners since they have been sexually active. Overall, 58 percent of men and 56 percent of women reported having more than five partners, and 29 percent of men and 23 percent of women reported having more than 14 partners. Some of the findings about the links between sexual history, height, and body mass were surprising and did not fall neatly in line with evolutionary or sociocultural theories.

The expectation that tall men, for example, would have the most sex partners was only partially supported. In fact, there was little difference in number of sex partners across the height continuum, with one exception--only very short men reported notably fewer median sex partners (5) than men of other heights (7). In terms of average number of partners, men who were average to extremely tall reported one to three more partners than men who were shorter than average.

"These findings confirm that height is relevant on the mating market," said David Frederick, Ph.D., assistant professor in psychology at Chapman University, and lead author on the study. "However, the relatively limited variation in sex partner number for men across much of the height continuum is difficult to explain. Research has repeatedly shown than women prefer men who are relatively taller than they are. It is possible that for most women there is a certain minimal threshold of height, after which they will consider a male as a potential sex partner, and thus men above that height will end up with similar numbers of sex partners."

With regard to men and body mass index (BMI), the study revealed that men in the middle BMI ranges had the most extensive sexual histories. According to Dr. Frederick, "Normal weight men and overweight men reported the most sex partners, and underweight men reported the least. Although it may be initially surprising that more overweight men reported the highest number of partners, it is important to note that the medical classification of overweight does not necessarily map onto social perceptions of overweight. For example, George W. Bush was medically classified as overweight during his presidency, but few people would perceive him as overweight. Men who appear somewhat larger, more powerful, or more athletic generally report more sexual experiences than other men."

With regard to women, underweight women had notably fewer partners than other women.

"There are numerous possibilities as to why underweight women had few partners," explained Dr. Frederick. " They may be highly dissatisfied with their weight and suffering from anorexia and thus not motivated to show their bodies; additionally, being underweight is associated with a relatively high mortality rate and/or they could be suffering from a variety of ailments that cause weight loss and thus have fewer sex partners because they are dealing with serious health issues."

The relationship between their height and number of sex partners revealed no revelations other than very short women reported fewer sex partners compared with tall women.

A total of 60,058 participants with a mean age of 37 completed the survey. Of those, 52 percent were men and 48 percent were women. The study examined height, education, age, and body mass index (BMI) as predictors of sexual history among heterosexual men and women. The research explored to what extent height and body mass are traits that may be useful social cues about health, social status and heritable fitness.