There are several factors that contribute to dark eye circles. Some of them are:
1) Age:
Aging is a natural process but also one of the causes of dark circles. Your skin tends to get thinner as you get older. During this process, your body may lose fat and collagen, which are responsible for skin elasticity. When this happens, the blood vessels beneath your skin may become prominently visible, causing the area to darken. (1)
2) Dehydration:
Dehydration is another factor that may cause dark eye circles. When your body receives improper or very little water, the skin beneath your eyelids becomes dull, and your eyes may look like they are sunken.
3) Fatigue or Poor Sleeping Habits:
When people go through disproportionate sleep cycles, they may lack energy or motivation.
Oversleeping or staying up a few hours before your usual bedtime can contribute to dark circles. (2)
Insomnia or sleep deprivation can make your skin dull and pale, allowing blood vessels and dark tissues to show below your eyes. Lack of sleep can also cause puffy eyes, due to which shadows may show up underneath your eyelids, which may appear as dark circles.
4) Allergies:
Certain allergic reactions allow your body to release histamine in response to harmful bacteria or viruses. The consequences of such allergies are eye dryness, itchiness, redness, and puffy eyes. The chemical histamine causes your blood vessels to dilate, making them more visible beneath your eyes.
Due to allergic reactions, one may develop the urge to rub or scratch their eyes. Doing this may worsen your symptoms and cause inflammation and broken blood vessels. This may result in dark shadows appearing below your eyelids.
5) Overexposure to Sunlight:
Getting out in the sun is normal and healthy. But it gets worse when one spends a lot of time doing that. Your body produces an excess of a pigment called “melanin” when you are overexposed to the sun, which is responsible for contributing to darker skin tone.
Hence, too much sunlight can cause pigmentation in the skin surrounding your eyes to darken.
6) Genetics:
Dark circles can also be seen in your family history. It can be an inherited trait generally noticed in early childhood, and it may worsen or slowly disappear as you age.
Other causes of dark circles are:
1) Smoking
2) Thyroid conditions
3) Anemia
4) Dermatitis