Well, yes, calcium deficiency can cause dark circles under your eyes. Nowadays, some evidences have shown that stress, lack of sleep, hereditary factors can be the common causes of dark circles.And some vitamin deficiency, calcium deficiency can cause them too. At this moment, you need to drink more milk to intake more calcium. Also, essential oils such as sesame oil can do a good job to your dark circles, for sesame oil contain a lot of nutrients such as vitamin e which are good for the dark circles under eyes.
Calcium is really important to our health. And it can help build to our bone and muscles. Get enough Calcium can make sure the correct heart beats, blood vessels dilate and prevent osteoporosis. And people who has calcium deficiency will suffer many problems include bone loss, numbness and muscle spasms, irregular heart rhythms and seizures and coma etc. But as far as i know that there is no proves that calcium deficiency cause dark circles under eyes. And usually, dark circles under eyes are result of lacking sleep, or too much smoking, too much drinking and some liver problems etc.