We’re constantly at battle with our sweat: trying to make it stink less, trying to stop it altogether during an important meeting, then trying to lose buckets of it on the road or trail. But if you stop and pay attention, all that perspiration can actually teach you a surprising amount about yourself and your health.
Here are a few things it could be trying to tell you:
1. You’re stressed
If you keep catching yourself sniffing and wondering, “Is that me?!,” take a second to reflect on what’s been on your mind lately. If you’re stressed or anxious, your pits are probably to blame. The sweat we produce when we’re hot is made by eccrine glands all over the body and contains mostly water and salt. But when we’re stressed, sweat is produced by apocrine glands, which are found only in certain areas like the armpits. That type of sweat contains fat and protein that mix with the bacteria on our skin, producing a stench in the process. Same deal if you’re anxious or scared.
2. You’re spreading happiness…
…or fear. Oddly enough, the people around you can pick up on what you’re feeling by the smell of your sweat. In a (rather revolting) experiment, 36 women smelled sweat samples of 12 men who had watched videos meant to either scare them or make then happy. When a woman smelled sweat from a guy who’d been scared by the video, she was more likely to make a facial expression resembling something like fear. When she smelled sweat from a happy guy, she was more likely to smile. Guess it can’t hurt to crack a smile on the road.
3. You’re at risk for heatstroke
Everything’s going swimmingly during your summer ride, when suddenly you realize you’ve stopped sweating and you’re starting to get dizzy. Anhidrosis, or the inability to sweat normally, can be dangerous, since it prevents your body from naturally cooling off. If you continue on without rehydrating, you risk heat illnesses like heat exhaustion or heatstroke. Move to a shady or air-conditioned space and have something cool to drink (without caffeine or alcohol). If you don’t start to feel better quickly, call for emergency medical attention.
However, longer-lasting anhidrosis may be due to nerve damage, certain medications, or an inherited condition, which can increase risk for heat illnesses and heart problems, too, says David M. Pariser, MD, former president of the American Academy of Dermatology. It’s pretty rare, though, he says; just because you don’t feel moist and clammy, doesn’t mean you’re truly not sweating. Turns out, most of us produce about an ounce and a half of sweat every day. If you notice a real drop in your sweat production, be sure to bring it up with your doctor.
4. Your blood sugar’s low
Normally, your blood sugar should be between 70 and 100 milligrams per deciliter, if measured when fasting. But if it drops below that 70 mark, whether because of diabetes or something like strenuous exercise, you may start to feel the effects. One symptom can be excessive sweating, or cold, clammy skin, particularly at the back of your neck at your hairline. (Watch out for a quickened heartbeat, shakiness, slight nausea, dizziness, and blurred vision, too.) Luckily, in cases of a mild dip, you can bring your blood sugar back up to normal by eating or drinking something. But if your blood sugar continues to drop, you’ll likely start to notice other more serious symptoms and could require medical care.
5. You’re eating the wrong foods
If you’ve been cursed with particularly fishy smelling B.O., you may have a rare genetic disorder called trimethylaminuria, which means your body can’t break down the chemical compound trimethylamine, produced during digestion of foods like eggs, legumes, and fish. Instead, your body sheds excess trimethylamine via sweat, urine, and breath—often producing a smell not unlike rotting fish, rotting eggs, or garbage, according to the National Institutes of Health. If you think you may have trimethylanminuria, work with your doctor to come up with the best treatment plan, which will likely involve avoiding these foods and possibly popping certain supplements.
6. You might need more to drink than your workout buddy
Ever had sweat drip into your eyes, only to find yourself in stinging pain? Does dried sweat leave a gritty feeling or white streaks on your cheeks, too? You’re probably a salty sweater, common among people who get lots of water during the day and keep sodium pretty low in their diet. You’ll probably want to reach for a sports drink or an electrolyte tablet you can dissolve in some H2O sooner than the average person.
7. You could have hyperhidrosis
If a doc can’t find an explanation for your excessive sweating, you may have a condition called primary focal hyperhidrosis, when excessive sweating is a medical condition in and of itself. And no, spinning enthusiast, you do not have hyperhidrosis if you can produce a lake of sweat under your bike. Primary focal hyperhidrosis is typically marked by sweating so excessive it interferes with your daily activities. “You’re supposed to sweat when you’re physically hot, or exercising, or stressed,” says Pariser, who’s also secretary and founding member of the International Hyperhidrosis Society. “People with primary hyperhidrosis sweat at times when they shouldn’t.” Even in a cool room, sitting perfectly still, a person with hyperhidrosis could have sweat dripping from her hands, he says.
Experts aren’t entirely sure why it happens, but they do know that hyperhidrosis runs in families and is the result of too much stimulation from the nerves that trigger the sweat glands. “The switch is stuck in the ‘on’ position,” Pariser says. Depending on the location of the sweating, hyperhidrosis treatment varies, but can include prescription-strength antiperspirant (even on the hands and feet), Botox injections, and surgery.
8. You could have lymphoma
Hyperhidrosis can also be a side effect of a number of health conditions—including gout, hyperthyroidism, and Parkinson’s disease—and even some medications. Particularly troubling is that it can be a symptom of lymphoma, or cancer of the lymph cells, which play a role in the immune system. It’s not completely understood yet why lymphoma can cause drenching sweat; it could be something about lymphoma itself or how the body responds to it, Pariser says. Perhaps it’s a reaction to another symptom—fever—as the body tries to cool itself down. (Both fever and sweating are known as “B” symptoms and linked with more aggressive lymphoma.) Or, it could be caused by hormones and proteins produced by cancer cells themselves, according to the UK Lymphoma Association.
This article originally appeared on Prevention.com.