Not every body handles heat the same

There's a phrase that keeps coming up every time a heat record falls: This is the coldest summer of the rest of our lives. It sounds extreme, but it's grounded in real science. Climate scientists acknowledge that a random future summer could still come in cooler than this one, but the overall trend is unmistakable: with warming already locked in and emissions still rising, summers will only keep getting hotter from here. Which means the one we just had, as brutal as it felt, may be as mild as it gets for a long time.

What doesn't get talked about nearly enough is that heat isn't a level playing field. Everyone knows the usual advice by now: check on elderly neighbors, keep kids hydrated, watch for anyone working outside. That advice exists for a good reason, and it saves lives. What you probably don't think about is that heatwaves also affect people navigating their menstrual cycle and people who depend on daily medication, things like antidepressants, blood pressure drugs, and diuretics.

Your body is not being dramatic

Women's bodies respond to heat differently than men's, and it starts with something as basic as sweat. Women, on average, sweat less and start sweating at a higher temperature than men do, according to research summarized by AOL¹. That sounds like a small thing until you realize sweating is the body's main cooling system. Less of it, later, means heat builds up faster and is harder to notice building up in the first place. Add in a naturally higher core body temperature and more insulating body fat, and women are already starting the heatwave from behind.

Now stack hormones on top of that. Estrogen actually helps your body release heat. Progesterone does the opposite: it makes it harder to sweat and cool down, according to Clue's breakdown of the science². And progesterone peaks right in the luteal phase, the week or so before your period, which is exactly when you're already dealing with bloating, fatigue, and mood swings. Heat then throws gasoline on that fire because it triggers inflammation throughout the body, which makes cramps and other PMS symptoms feel worse.

This isn't some fringe theory. A 2025 presentation at the UK's Physiological Society conference³ laid it out clearly: elevated progesterone during the luteal phase raises resting body temperature and delays the point at which your body starts sweating and cooling itself. The same talk pointed out that women may need longer to acclimate to heat than men do and that caregiving duties often make it harder to actually rest or cool off during a heatwave. The researcher's bigger frustration was that female bodies are still wildly understudied in heat research, mostly because hormones are "complicated" to control for in a study. That complexity is exactly why the gap in guidance exists.

It goes beyond feeling miserable, too. Heat stress has been linked to irregular cycles, hormonal imbalance, and reduced ovarian function, per a review published in ScienceDirect⁴. People with PMDD, endometriosis, or menstrual migraines face even more risk on top of that, and none of that shows up in a typical heat advisory.

Daily medications quietly mess with your thermostat

The second group flying under the radar: anyone who depends on a daily medication to manage their health. Antidepressants, blood pressure drugs, water pills, allergy medication—it's a longer list than most people realize, and the mechanism is completely different from the hormonal one above. All of it lands you in the same spot, though: a body that struggles to cool itself down.

Antidepressants can interfere with how well your sweat glands work; some of the most commonly prescribed ones can push core body temperature into dangerous territory, according to Medical News Today⁵. That's genuinely in the heatstroke range. Blood pressure medications work against you in a different way: some reduce blood flow to the skin, which blunts the body's ability to shed heat, while water pills flush out fluid and electrolytes, making dehydration far more likely, according to INTEGRIS Health⁶. Even something as ordinary as an allergy pill can reduce your ability to sweat.

It's not just one type of medication either. Certain psychiatric medications and ADHD medications have also been shown to shift how much heat someone can tolerate before it becomes dangerous, and part of the problem is that these drugs can blunt your own sense of how hot you actually are, according to Remedy Psychiatry⁷. You can be in real trouble before you feel like anything is wrong. There's an added wrinkle with antidepressants specifically: raising the dose or combining medications that affect the same brain chemistry can trigger a dangerous reaction that looks a lot like heat stroke (racing heart, sweating, confusion, fever), so it's easy to mistake one for the other and delay getting help.

Not everyone treats this as a five-alarm fire. One family physician told WAFB⁸ that patients on antidepressants generally still regulate their core temperature fine; they just sweat noticeably more to get there. That's reassuring on its own. But stack a daily medication on top of a blood pressure condition, a heatwave, and the luteal phase of someone's cycle, and you've got real layered risk.

Heat hits everyone differently

The reality is that heatwaves aren't just hot; they're personal. They hit different bodies in different ways, and the standard advice doesn't always cover the full picture. That doesn't mean we should panic. It means we should pay attention to our own bodies and to the people around us. We need to start having real conversations about these things, because the more we understand how heat affects us all differently, the better we can look out for each other. The hottest summers are still ahead, but knowing how heat really works is the first step in making sure we all get through them safely.