Calcium deficiency can cause cramps because calcium ions are very important ions that stabilize nerve cell membranes and reduce nerve and muscle excitability. When calcium deficiency causes increased excitability of nerves and muscles, it can cause muscle spasms and cramps. If the cramps are caused by calcium deficiency, you should eat more calcium-rich foods, get more sunlight, take vitamin D supplements, and improve calcium deficiency with calcium supplements. If the calcium deficiency is caused by other diseases, the primary disease needs to be treated. However, besides calcium deficiency can cause cramps, some other causes can also cause cramps, such as overexertion, high fever, localized vascular nerve compression, epilepsy, etc. All of these can cause cramps. Therefore, if you have cramps, you should go to a regular hospital in time. If it is caused by calcium deficiency, take calcium supplements in time. If the cramps are caused by other reasons, the primary disease needs to be treated.