Whether it was caused by a night out with friends, a crying baby, or plain old insomnia, we all know that lack of sleep affects our bodies. In addition to fatigue and a yearning for coffee, poor sleep can leave us frowning at the dark, swollen circles under our eyes. Some of us are so bothered by these “eye bags” that they go to extreme lengths to try and remove them with moisturizers, chemical peels, or even skin bleaches.
But eye bags and dark circles differ in important ways. The swelling under our eyes that causes “bags” is usually due to environmental factors, like poor sleep or too much salt. Dark circles, however, are influenced by the structure of our face, and while a bad night’s sleep can accentuate them, some people can sleep like a baby every day and still retain dark circles.
Understanding the causes of eye bags and dark circles can help determine whether they need to be treated or simply recognized as part of the natural diversity of the human face.
Why we care about eye bags
The inch or two of skin under the eyes plays an outsized role in subtle social status signals, says Tanuj Nakra, an oculofacial plastic surgeon at Dell Medical School at the University of Texas at Austin.
“When there is darkness in the under-eye region, it can convey unintended psychological states or emotions or physical states, such as being tired, being sick, being sleepy and uninterested, or having serious medical conditions, like cancer or liver diseases,” he explains.
But that’s not always the case. Many young, healthy, and well-slept people can also have dark circles under their eyes. To understand why, we have to dive under the skin to the layers of bone and muscle that make up the face. At the lower edge of the eye socket sits an important ligament, the orbicularis retaining ligament (ORL), which holds our under-eye skin in place. Some people, says Nakra, are simply born with a tighter ORL, which shows up more under their skin, making dark circles appear in the under-eye region.
Dark circles may also result from naturally thin, pale skin near the eyes. This may make the orbicularis muscle—a sunglasses-shaped structure that helps us blink—more visible. This darker color can be seen through the skin as dark circles.
How bad sleep worsens eye bags
A tighter ORL, pale skin, and visible orbicularis muscle are all traits we might inherit from our parents, which can create the appearance of dark circles. Nevertheless, these inherited dark circles are often unfairly lumped in with the effects of poor health or sleep, explains Nakra.
When we have a particularly salty meal or a bad night’s rest, our faces can be subtly altered by swelling, or, as scientists call the phenomenon, edema. Under our face lies a constantly shifting river delta of blood vessels and arteries that carry vital oxygen to our tissues. “These arteries tend to be slightly leaky, and they leak fluid out of the arteries into the tissues,” says Nakra. This swelling can cause eye bags, and accentuate the appearance of naturally dark under-eye skin.
Poor sleep isn’t the only environmental factor that can lead to under-eye bags. Separating our external skin and ligaments is a layer of fat. Severe malnutrition leads to a loss of this fat layer, which can increase the visibility of the underlying ligaments, increasing the appearance of dark circles.
To a lesser degree, natural aging can lead to thinner skin and reduced facial fat and firmness, which can accentuate both eye bags and dark circles.
Hyperpigmentation, where some areas of the skin are darker than others, can also cause dark circles. Cells, called melanocytes, dictate our natural skin color through their release of the pigment melanin. “People can get hyperpigmentation in their under-eye region from inflammation around the eyes, from sun exposure, from irritation,” says Nakra. That means people with darker skin are at greater risk of developing melanin-linked dark circles under their eyes.
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In rare cases, a chemical damaged red blood cells release, iron-rich hemosiderin, can cause dark circles.
Diseases like chronic venous insufficiency, in which damaged veins struggle to return blood to the heart, can lead to weakened circulation and hemosiderin leaking into the area under the eye. This type of discoloration can also appear throughout the body due to chronic disease or trauma.
How to deal with eye bags
Nakra says if eye bags or dark circles do turn out to be symptoms of an underlying disease, they can be useful indicators for future treatment. Lifestyle changes can help reduce puffy eyes. Another option is to reach for eye creams containing chemicals like caffeine, which reduces blood flow into the surrounding skin and helps calm swelling.
If dark circles are due to structural facial features, options are more limited. Thin skin can be masked with concealer, and some expensive eye creams use chemicals that disrupt light passing through the skin, further reducing the purple coloring of the underlying muscle. But sometimes the only option is to embrace our face’s distinct features.
So, next time you wake up and look in the mirror, remember that eye bags and dark circles can be a natural trait of our faces, as distinctive as freckles or beauty spots.
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