Like varicose veins, dark circles under the eyes are usually an inherited trait. The skin under the eye is very thin. When blood passes through the large veins close to the surface of the skin it can produce a bluish tint. The more transparent the skin also an inherited trait the darker the circles appear. In people with a deep-set bone structure, shadowing contributes to the dark color under the eyes.
Any medications that cause blood vessels to dilate can cause circles under the eyes to darken. Because the skin under the eyes is very delicate, any increased blood flow shows through the skin.
The lack of nutrients in the diet, or the lack of a balanced diet, can contribute to the discoloration of the area under the eyes. It is believed that lack of mineral iron can cause dark circles as well. Iron deficiency is the most common type of anemia and this condition is a sign that not enough oxygen is getting to the body tissues.
The skin can also become more pale during pregnancy and menstruation (due to lack of iron), which again allow the underlying veins under the eyes to become more visible.
A lack of sleep or excessive tiredness can cause paleness of the skin, which again allows the blood underneath the skin to become more visible and appear more blue or darker.
Some skin care experts say that fatigue has nothing to do with the dark circles, but it has to do with when one lies down since gravity can cause fluid to collect in the lower eye lid.
Dark circles are likely to become more noticeable and permanent with age. Excess folds of skin under the eyes will also make dark circles more pronounced.
Another cause may be bad blood circulation. Cardio exercise increases blood circulation and may help the dark circles to disappear.
Dark eye circles could be a sign of excessive loss of water from the body (dehydration).
Simple Home Remedies found in your kitchen
Although to date, there has been no end-all to curing or reducing dark circles, there are many home-made ingredients that can help make the dark circles less visible. For example it is said drinking plenty of fluids and a lot of rest can suffice.
Put tea bags under the eyes for 20 minutes everyday. You can just wet the bags with lukewarm water and place it under the eye when it has cooled down or chilled.
Potato Juice is one of the best way to reduce dark circles. Grind the potato and apply it immediately for 20 minutes everyday with the help of a cotton. You will see results immediately and within a couple of weeks much improved results.
Cucumber Juice is another way which is widely known and most used. Grind the cucumber and apply the juice with the help of cotton for 20 minutes, this also gives a good result.
One treatment is to massage almond oil with honey around the eyes before going to bed. This will lighten the skin around eyes and brighten it considerably. Also, try gentle massage around eyes while taking shower. The steam from the shower helps for effective massage. However, some say that the constant rubbing will only cause the circles under the eye to become worse.