Joint pain is one of the common symptoms of calcium deficiency in adults, joint pain usually develops slowly, if the joint pain is mild, it can be improved by taking calcium tablets and calcium containing foods. The bones will become weak and flabby due to the lack of calcium, and thus the symptoms of osteoporosis will appear. Adults with calcium deficiency may also suffer from body cramps. Muscle spasms can easily occur with low blood calcium, inducing hand and foot convulsions, and due to the large amount of calcium ions or low blood calcium entering the cells, there will be serious interference with the function of nerve cells, leading to their increased excitability and finally convulsion symptoms.