There are a number of factors that contribute to the appearance of dark circles under eyes. Some common causes include:

Fatigue

Excessive sleep, extreme fatigue, or just staying a few hours after your usual sleep time can cause dark circles under the eyes. Lack of sleep can cause your skin to become pale and bloodless, allowing dark tissues and blood vessels to be seen beneath your skin.

Lack of sleep can also cause fluid to build up under your eyes, making them look swollen. As a result, the dark circles you see may be shadows created by your swollen eyelids.

Age

Natural aging is another common cause of dark circles. As you age, your skin becomes thinner. You also lose fat and collagen necessary to maintain skin elasticity. As this happens, the dark blood vessels under your skin become more visible causing the area under your eyes to darken.

Eye strain

Looking at a TV or computer screen can cause significant eye strain. This type of exertion can cause an increase in blood vessels around the eyes. As a result, the skin around the eyes can darken and make you have dark circles.

Allergies

Allergic reactions and dry eyes can cause dark circles. When you have an allergic reaction, your body releases histamines in response to harmful bacteria. In addition to causing unpleasant symptoms - including itching, redness and swollen eyes - histamines also cause blood vessels to dilate and become more visible under your skin.

Allergies can also increase your desire to rub and scratch the skin around your eyes. These actions can worsen your symptoms, causing inflammation, swelling and damaged blood vessels. This can lead to dark shadows under your eyes.

Dehydration

Dehydration is a common reason why dark circles occur. When your body does not receive the right amount of water, the skin under the eyes begins to look dry, and the eyes look sunken. The reason for this is the proximity of the eyelids and bones.
Excessive sun exposure

Excessive sun exposure can cause your body to produce excess melanin, the pigment that gives skin color. Too much sun - especially for your eyes - can cause darkening of the pigmentation of the surrounding skin.

Genetics

Family history also plays a role in the development of dark circles. Dark circles can be a hereditary trait seen in early childhood, and can get worse as you get older or slowly disappear. Predispositions to other medical conditions - such as thyroid disease - can also result in dark circles under the eyes.

For many people, dark circles are temporary and are often a sign of aging or lack of sleep. There are a number of home remedies for dark circles under eyes you can find. However, if the discoloration or swelling gets worse over time, make an appointment with your doctor or dermatologist to make sure you have correctly diagnosed the problem and received the best treatment.

Very educative

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one of the main reason is lack of sleep in the night time is the reason for dark circle near the eyes. Most of the time, My friend also facing this issue. Applying so much of artificial products in the face also some times cause the dark circle near the eyes.