When you're dressed for the cold weather in layers of fleece leggings, and practically mummified by a floor-length puffy coat, the last thing you want to do is peel off all your cozy clothes just to go to the bathroom. But because fate is cruel, cold temperatures often make you feel like you have to pee more often than usual. It's strange to be shivering and have a bladder that's about to burst, but there's a physiological reason why your bladder quivers in frigid temps.
Scientists have dubbed this phenomenon "cold-induced diuresis," which basically means an increase of urine caused by the cold. When you're exposed to cold temperatures, your blood vessels constrict in order to concentrate blood flow around your vital organs, and away from your skin. As a result, this shift also causes your blood pressure to rise.
So, what does this all have to do with peeing? Well, we know that the kidneys are responsible for filtering waste out of your blood and creating urine, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The kidneys filter about a half-cup of blood per minute, and about 150 quarts of blood a day. Most people produce 1-2 quarts of urine a day on average, according to the NIDDK. However, when it's cold outside, your kidneys have more blood to filter than normal because there's more blood pumping through your body. So, they end up producing more urine, and you have to pee more frequently.
Annoying as it is to be stuck outside and needing a bathroom, cold-induced diuresis is just one way that your body protects you from the cold. Some experts believe that increased urination is one warning sign of hypothermia, which is a dangerous condition caused by your body losing heat faster than it can produce. If that's the case, and you are experiencing the other telltale signs of hypothermia (such as, shivering, slurred speech, shallow breath, and a weak pulse) it's important to get to a warm, dry location and seek medical attention immediately, according to the Mayo Clinic.
But if you're just outside on a cold day and get the urge to pee, you should probably find a bathroom and do your business ASAP. Because the only thing that's more uncomfortable than needing to pee is ending up with a urinary tract infection from trying to hold it too long — or, peeing on yourself.