Tiredness, working too hard or even just staying up late can cause dark circles, but it can also be down to genetics. Some people will simply have dark circles around their eyes thanks to their genes. While not much can be done to change your genes, a number of things, including a good skin care routine, can be done to prevent the area around the eyes from looking even darker.
Another problem that goes hand-in-hand with dark circles is eye puffiness, aka bags below your eyes. Sometimes the blood vessels around your eyes can get damaged, blood leaks out, and you’re left with puffy dark circles or a puffy eye. In some people, this is caused by fluid buildup below the eyes, either due to illness, medical treatment, allergies or excessive salt consumption, which can result in the body retaining more fluid than usual. If you do suffer from allergies, or have ever had an allergic reaction, you're probably very aware of this. This can place increased pressure on the skin and blood vessels around the eyes, affecting blood flow and forcing blood vessels closer to the surface of the skin. The result: dark under-eye circles appear more prominent. As such, eye puffiness can also simply be a result of old age, just as we might become more aware of wrinkles, or the odd crow foot.
Simply put, dark circles are a result of the thin layer of skin below your eyes showing the blood vessels and the blood they contain more clearly than anywhere else on your body, so can be affected by blood flow. This skin around your eyelids, called peri-orbital skin, is on average about 0.5 mm thick compared to an average of about 2 mm thick on most of the rest of your body. The reason veins appear to be blue on some complexions isn’t because the blood inside them is blue; it’s because your skin or subcutaneous tissue only lets blue wavelengths of light pass through it. As a result, only blue light is reflected back and the veins look bluish. For the same reason, veins can look green or brown in other complexions.
It’s the exact same concept with the skin below your eyes. Those dark bluish circles are (usually) just the result of light being reflected back off of the blood vessels sitting just below the surface of that incredibly thin patch of skin. This is the same reason facial bruises are more prominent below or around the eyes; the thin skin just shows the blood from the ruptured blood vessels a little bit more clearly.
As we age our skin loses its elasticity and ability to regenerate and as a result, it becomes thinner. This is why more often than not, elderly people will not only have more prominent wrinkles, but also peri-orbital dark circles regardless of how much they sleep. As with those who are genetically predisposed to having thinner skin below the eyes, a dark eye circle can just be biology.
- Peri-orbital Hyper-pigmentation
Another thing that can cause dark circles beneath the eyes is something known as peri-orbital hyperpigmentation, which is a condition that results in more melanin being produced by the skin below the eyes, resulting in it appearing to be a darker colour. This is mostly a condition that affects (or is at least more noticeable in) darker skinned people.
When the body is tired, or you're suffering from a lack of sleep, production of the hormone cortisol is dramatically increased to help give you the energy you need to stay awake. Among many other things, cortisol increases the volume of the blood in your body, which causes the blood vessels (including the ones below your eyes) to accommodate it. As we’ve already mentioned, dark circles are mostly caused by us seeing our blood vessels through our skin, so it stands to reason that when those blood vessels are engorged, they’d be easier to see, even in people who may have been blessed with thicker skin below their eyes. For some people, this is amplified when they have a lack of sleep.
Other things that can contribute to dark circles under the eyes include: medication or treatment that causes blood vessels to dilate; scratching or rubbing your eyes excessively (especially during allergy season) regularly sleeping on your stomach and liver disease.
