Yes, castor oil or olive oil is good for dark circles, because both of them can provide nutrient to the skin, especially for the dry skin. Apply 2-3 castor oil, warming slightly, mix with or without rose water, immerse cotton pad, and then cover the pad over eyes for 20 minutes. And you can also use shelled potato or cucumber. Apply them for 2-3 weeks, and the dark circles will lighten. Besides, foods contained vitamin A, B2 and C can improve blood vessel. Do not forget to drink enough water every day. Castor oil is also good for hair, eyelash and stretch marks.
Being a transparent viscous liquid, Castor oil has the little symplectic taste. Using castor oil can treat the dry knot, itching boils and burns. Its inner elements contain Ca, Fe, Si, Al, Cu, Mg, Zn and so on. It can be used to the clean the intestines and stomach for the intestinal dry constipation. As we know, the black circles under the eyes are always caused by the not good circulation of the body, staying up late at night or drinking too much the night before. The main role of castor oil for the black circles under the eyes is to clean the stomach and intestine which will make the blood circulation go on well. Thus, the melanin will be released and the black circles under the eyes will be disappeared. If you have the black circles under the eyes, you could have a try of using the castor oil.
Yeah, the castor oil can be good for treating the dark circles. The dark circles you get may be probably caused by the lack of sleep, too much water before the sleep and so on. When you find you get the castor oil, you can use the little part of castor oil on your eyes surrounding parts until it is attracted. It may release the symptom.