Why are women always cold?

Dear Cecil: I need to know why the women in my office always seem cold while the men are warm. The women are always wearing light sweaters (even in summer) and complaining about the air conditioning. Last summer I called maintenance to have them adjust the temperature, which was 25 degrees Celsius (or 77 degrees Fahrenheit), down to 21 (room temperature), only to be confronted by several cold women. Why are they always so cold? I have tried to tell them that their constant dieting (i.e., skipping lunch and eating too much salad, while sneaking in the occasional cookie or two) not only doesn’t help them lose weight but lowers their metabolism and promotes poor blood circulation. In response, they tell me they’re cold because of their monthly period. As that can account for only about a week of every month, I think they’re wrong. Please try to settle this. Harold Ykema, Toronto, Canada

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Illustration by Slug Signorino

Cecil replies:

Excuse me, Harold. Did you say you were working in an office or a morgue? Assuming it’s the former, I have to tell you that clinicians regard temperature sensitivity in men as a classic diagnostic sign, as follows:

  • Prefers, or at least puts up with, 25 degrees Celsius (77 degrees Fahrenheit) = manly man.
  • Prefers 21 Celsius (70 Fahrenheit) = pathetic sniveling puss.

That said, women do seem to like a higher ambient temperature than men. Popular belief holds that men have a “higher metabolism,” which may be broadly true but in itself explains nothing. The medical literature offers more detail, but even the experts don’t agree. Leading theories:

Women have a higher ratio of surface to volume than men and thus shed heat faster. The reasoning here is that heat generation is determined by volume (radius cubed), while heat dissipation is determined by skin surface area (radius squared). The smaller your size, the lower your heat generation/heat dissipation ratio, and the colder you are. Probably part of the answer — see below.

Men have more heat-generating muscle mass. Muscles are well supplied with blood vessels. The more muscle, the more blood flow and the more warmth.

Women have a higher vasoconstriction threshold temperature. Vasoconstriction is the process by which, as the external temperature falls, blood flow to the skin is restricted in order to divert blood to internal organs, thus maintaining core temperature. The theory: as ambient temp falls, women shut off blood flow to the skin sooner in order to provide more warmth to their unborn babies, so they feel colder. Interesting idea but as yet unproven — though women do seem to have lower skin temperature when exposed to cold.

Women get colder during menstruation. Supposedly this is due to anemia, hormonal changes, etc. However, most studies haven’t shown much difference between menstruating and nonmenstruating women in terms of heat response. As you say, female aversion to cold doesn’t seem to be confined to a particular time of the month.

I’ve also heard it claimed that men feel warmer because they wear three-piece suits and get offices with south-facing windows, whereas women are apparently shivering in rags in the dark. Setting aside the gross generalizations in this picture, when’s the last time you saw anybody except a lawyer wear a three-piece suit?

The most persuasive research (for example, “Comparison of Thermoregulatory Responses Between Men and Women Immersed in Cold Water,” Tikuisis et al, Journal of Applied Physiology, October 2000) suggests that varying male/female response to temp is largely a result of size and body-fat percentage, not some fundamental biological difference. Men have a higher metabolism only in the sense that a big car uses more gas than a little one. (To be fair, you can find studies that point to a different conclusion — as I say, the experts disagree.) Anyway, you can either work with large (or no) women, be a pig, or deal with it. Personally I like 25 degrees Celsius just fine.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.