There is a common belief that women generally feel colder than men, but is this really backed up by science?
In fact, the evidence is mixed, in part because few studies addressing this question have been conducted in a carefully controlled manner. This means that the data collected to date suggest that human perception and the ability to regulate the body temperature it is not based on their gender, but rather on their physical characteristics – especially their body fat and surface area.
Lots of past research It seems to support the idea that women often feel colder than men. This included survey-based studies that examined people’s preference thermostat temperature in office setting.
Research also suggests that women have slightly higher core temperatures than men on average, but their hands, feet and ears tend to be colder. This may be related to the two main female sex hormones: estrogen and progesterone. Estrogen dilates blood vessels in the limbs, allowing heat to escape; meantime, progesterone can constrict blood vessels in the skin, which increases core temperature but reduces blood flow to the extremities.
Related: Has the average human body temperature always been the same?
This explanation suggests why women may feel colder than men—but again, there’s probably more to the story.
Several recent, well-designed studies found that the regulation of a person’s body temperature depends less on their gender and more on their physical characteristics. For example, in a small study published in a journal PNASResearchers at the National Institutes of Health (NIH) have found evidence that women and men perceive temperatures in similar ways and show no major gender-based physical differences in how they respond to the cold.
“We were trying to figure out what happens at the temperature where people start shivering — where they’re cold but not overtly shivering,” said the study’s lead author. Robert BrychtaNIH Scientist.
In the study, 12 women and 16 men, all relatively thin, each remained in a room while the researchers varied the temperature from hot to cold—from about 88 degrees Fahrenheit (31 degrees Celsius) to about 63 F (17 C). Participants wore standardized clothing as well as sensors that monitored electrical activity in their muscles and skin temperature.
The “calorimeter” measured the amount of oxygen people breathed in and the carbon dioxide they exhaled; this helped the researchers monitor the amount of energy expended. Body weights, heights, body fat percentages and basal metabolic rates were also recorded as these factors affect heat production.
Participants also rated their perception of room temperature using a visual sliding scale from “very cold” to “very hot.”
The temperature perception of men and women was the same throughout the experiment, and they also shivered to the same extent at lower temperatures. The coldest temperature they endured before shivering was the same, about 20°C to 21°C.
The participants’ skin temperatures were similar throughout the experiment, although on average the women had slightly warmer skin than the men. Other physiological measurements—such as the electrical activity of their muscles—were also essentially the same, but the women’s basal metabolic rates were slightly lower than the men’s.
Females maintained slightly higher body temperatures at low temperatures than males. This may be because, on average, women had a higher percentage of body fat than men, and therefore more isolation, the researchers said in the paper. The temperature at which women’s bodies began expending energy to keep warm — what the researchers called the lower critical temperature — was also a touch lower than men’s, about 1.8 F (1 C) on average.
Overall, the results suggest that women and men respond similarly to changes in temperature. Any differences you may observe in individuals are due to their individual differences in body composition.
“It’s the interaction of body surface area and body fat percentage that contributes to where the critical temperature falls,” Brychta told Live Science, not a person’s gender. “Even though we see some differences between men and women, it’s really like an individualized point.” For example, a taller woman with less body fat is likely to have a lower critical temperature than a shorter man with more body fat.
The study led by Brychta and his colleagues was small in size, but it begins to challenge the notion that women always feel colder than men, writ large.
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