You might think that the worst thing about not getting sleep is being tired. And that definitely isn't ideal. But, according to a small new study, one night of tossing and turning may also have unexpected effects on your body. For the study, recently presented at this year's meeting of the Radiological Society of North America (RSNA), researchers took blood and urine samples from 15 participants before and after a 24-hour radiology work shift. During that shift, participants got an average of three hours of sleep. The researchers also took measurements of participants' blood pressure and heart rate. Their results showed that, after going 24 hours with just a few hours of sleep, participants' blood pressure and heart rate were both elevated. Plus, the blood and urine samples showed elevated levels of cortisol (a hormone associated with the body's physiological response to stress) and several hormones related to the thyroid gland, which helps regulate many processes in the body, including temperature and metabolism. There are a few big drawbacks here, though. First, everyone in the small group of participants were radiologists. That means they're probably not representative of every kind of night-shift worker out there. Also, the researchers didn't examine the effects of sleep deprivation after 24 hours, so we don't know for how long the heart-related changes stick around. Participants may have totally recovered after a night or two of quality sleep. But this isn't the first time sleep deprivation has been linked to heart issues: Regularly getting fewer than six hours of sleep every night has been shown to increase your risk for a stroke and a heart attack. And other research suggests there may be other short- and long-term consequences to skipping sleep. For instance, one all-nighter can affect your memory, your personality, and your circadian rhythm. So the bottom line is the same as it's always been: Good sleep is essential — for way more than just energy.