The best time of the day for adults to take calcium is 2-3 hours before bedtime or 1-1.5 hours after dinner, when the concentration of gastric acid secretion is high and calcium ions are easily absorbed in the divalent state. Calcium deficiency can easily cause occipital baldness, restlessness, excessive sweating, difficulty in sleeping, easy to wake up, etc. You can find out if you are deficient in calcium through trace element testing. Some calcium supplements, such as calcium carbonate, are relatively poorly soluble, so it is recommended that they be taken 0.5-1 hour after a meal, with better results when taken in divided doses. Calcium gluconate or calcium lactate has a better taste but relatively lower calcium content, and is also recommended to be taken after meals for better performance and cost effectiveness. In addition, the absorption of calcium is related to the nutritional status of vitamin D. Patients taking calcium are also recommended to take vitamin D at the same time to promote the absorption of calcium. It is also important to pay attention to more sunshine and consume more calcium-containing foods, such as milk, soybeans and animal bones in general.