Calcium requirements vary for various groups of people because of their different ages and physical conditions. In general, the daily intake of calcium for people aged 18 to 49 is about 800 milligrams. For people over 50 years of age, the daily intake of calcium is about 1,000 milligrams. If you are pregnant, you should consume about 1,000 milligrams of calcium per day during your second trimester, and 1,200 milligrams per day during your second trimester and when you are breastfeeding. The reason for the different calcium requirements is that different people have different intestinal calcium absorption capacity, different needs for growth and development, and different calcium loss. It is recommended to supplement calcium through diet, such as milk, nuts, fish, shrimp and shellfish with high calcium content, etc. It is also recommended to do outdoor exercise in moderation and take vitamin D supplement to help the body better absorb and utilize calcium, and improve the utilization rate of dietary calcium intake.