Research shows that men have grown twice as much as women over the past century

Amid the profound changes humanity has experienced, you could be forgiven for not paying attention to the rise of sexy and formidable men: those tall, broad-shouldered types who are strangers to self-doubt.

But according to a new study, men around the world have grown in height and weight twice as fast as women over the past century, widening the gap between the sexes.

“We are seeing insights into how sexual selection has shaped the male and female bodies and how improved environments, in terms of food and a lower burden of disease, have freed us from our shackles,” says Prof. Lewis Halsey from the University of Roehampton. .

Halsey and his colleagues used data from the World Health Organization, foreign authorities and British data to see how height and weight have changed due to living conditions. The latter was measured using the Human Development Index (HDI), a score based on life expectancy, education time and per capita income, which ranges from zero to one.

Analysis of data from dozens of countries found that for every 0.2 point increase in HDI, women were on average 1.7 cm taller and 2.7 kg heavier, while men were 4 cm taller and 6.5 kg heavier. This suggests that as living conditions improve, both height and weight increase, but at more than twice the rate in men than in women.

To see if similar trends were playing out within countries, the researchers dug into historical height records in Britain, where the HDI rose from 0.8 in 1900 to 0.94 in 2022. During the first half of the century, average height rose of women by 1.9%, from 159 cm to 162 cm. , while the average male height increased by 4% from 170 cm to 177 cm.

“To put this in perspective, about one in four women born in 1905 were taller than the average man born in 1905, but this dropped to about one in eight women for those born in 1958,” Halsey said.

To write Biological letters In a study titled “The Sexy and Formidable Male Body: Men’s Height and Weight Are Condition-Dependent, Sexually Selected Traits,” the scientists speculate that women’s sexual preferences may have fueled a trend toward taller, more muscular men — though In an age of obesity, heavy does not necessarily mean muscular.

Stature and physique are important indicators of health and vitality, Halsey said, while sexual selection also favors males who are better able to protect and defend their mates and offspring from others.

“Women may find men’s height attractive because it potentially makes them more formidable, but also because their height signals that they are well made,” says Halsey. “As they have matured, they have not been affected by the slings and arrows of a bad environment, so they have achieved more of their height potential. It is an indication that they are well made.”

The findings build on previous work Women want taller men more than men want shorter women. But there are downsides to being tall. Although taller people tend to earn more, they are also more susceptible to several forms of cancer, possibly because they have more cells that can accumulate mutations that lead to the disease.

Michael Wilson, a professor of ecology, evolution and behavior at the University of Minnesota, said the faster increase in height and weight in men was “striking.” He said this is consistent with the long-standing idea that females are “the most ecologically limited” sex due to the demands of reproduction, especially in mammals where pregnancy and lactation are “energetically expensive.”

“Investments in larger body size by males appear to be sensitive to nutritional conditions,” he said. “When men grow up eating more energy-dense foods, they develop larger bodies, to a greater extent than women.