2. You Didn’t Sleep Well Last Night
We know you know this already, but it bears repeating: A bad night’s sleep could make your eyes appear swollen in the morning, especially if you’re stressed. “When you’re under stress, you release cortisol from your adrenal glands, and that changes the salt balance in the body,” says Swann. Because your salt balance is off, you might retain water and swell.
3. It’s Allergy Season
Puffy eyes are a common symptom associated with seasonal allergies. When you have an allergy, your body goes into full-on attack mode by releasing histamine into your system. In some cases, when histamine releases into the skin, it causes a hive-like reaction, especially around the eye area, says Swann.
4. It’s That Time of the Month
Blame it on the PMS! Similar to how the rest of your body bloats during your monthly cycle, your eyes can retain water as well, says Swann. Like belly bloat, eye swelling caused by your period generally goes away after a few days.
5. You Were Crying
We know it’s a no-brainer, but here’s the science behind it: Puffiness from crying is a result of your eyes’ lacrimal glands working overtime to produce tears. “When this gland is churning out tears, the [tear] fluid is less salty and more watery,” says Swann. “Differences in salt concentration between these tears and the surrounding tissues causes some swelling of the eyelid.”
6. You Overdid It at Happy Hour
The eyes are vulnerable to many small changes in diet, says Swann. Alcohol, for example, could cause your body to get dehydrated and make your eyes dry, too. People who eat a lot of salty foods can also retain water in their eye area, which gives them a little puffiness.
7. You Have a Thyroid Problem
Most of the time, puffy eyes aren’t a big deal, but they can be a side effect of a bigger health issue. “Patients with some types of hyperthyroidism can get thickening of the fat around their eyes, causing puffy eyes,” says Swann. “Puffy eyelids can also be seen in lupus, dermatomyositis, and other connective tissue diseases.”
How to Get Rid of Puffy Eyes
In most cases, it’s a relatively easy fix. Swann says any eye cream—like Skinmedica TNS Eye Repair ($ 61, amazon.com)—can help diminish puffiness and thicken the collagen around your eyes. For instant relief, Swann suggests soothing your eyes with cucumbers or cold tea bags for about 15 minutes. “Cold in general decreases inflammation, so it slows down the process of histamine release and inhibits swelling,” says Swann. In the case of hormonal puffiness, an eye cream may not totally do the trick (you’ll have to wait things out), but it can still ease things slightly. And if you have allergies or a thyroid condition, treating the underlying issue under the care of an M.D. can also help.