In the clinic, you will encounter this conversation: “My daughter looks much shorter than her peers, do you want to take more calcium supplements?” Why do we need to give calcium to our children? When asked this question, many parents would say, “Calcium supplements can make your child grow taller.” In the parents’ opinion, calcium is the most important element to promote the growth of children. Is this really the case? When should I take calcium supplements? There are several peak periods for calcium: First, infancy and early childhood, when growth is fastest, with weight up to three times the birth weight and height up to 1.5 times the birth height at the age of one, so the demand for calcium is quite high. Second: the peak period is puberty, which is also the second peak of growth, at this time, the average annual height growth of 10-20 cm. Third: the peak period is some special periods in adulthood, menopause, old age due to the reduction of hormone secretion in the body, calcium absorption rate decreases, prone to osteoporosis, need more calcium; pregnancy and breastfeeding also increase the need for calcium. When should children start taking calcium supplements? In recent years, the time to start calcium supplementation has been advanced time and again. 50 years ago, calcium supplementation started 3 months after birth; 20 years ago, it was advanced to 40 days after birth; currently, it has become a consensus among pediatricians to start calcium supplementation half a month after birth. The daily calcium requirement for infants is 600-800 mg, 800-1000 mg for ages 3-10, and 1000-2000 mg for adolescence. The human body grows taller mainly by the linear length increase of bones, which needs calcium to grow, and the amount of calcium also determines the hardness of bones; if there is not enough calcium, the bones will become soft. However, calcium is not the main driver of bone growth. Bone growth depends on growth hormone and the protein and nutrients obtained from food. Children who are deficient in growth hormone will not grow taller even if they have enough calcium, and those who do not have enough total energy and protein will not grow taller with calcium only. Therefore, growth is not only related to calcium supplementation, but growth hormone and other growth-related factors need to be evaluated thoroughly. If your child has growth retardation, do not take calcium supplements indiscriminately, but seek medical advice to find out the exact cause.