Calcium is an essential mineral for both children and adults. It is vital for the development of bones; teeth; muscles; heart; and the nervous system. It also transmits electrical messages from our brain to the rest of our body. 99 per cent of it can usually be found in our bones and teeth, but calcium usually comes from external sources such as food or supplements as our own body is incapable of producing it.

They need as much as a child does-especially as they undergo organogenesis (transformation of a mass of cells into an organ in the developing embryo).

It is estimated that a full-term fetus in its 3rd trimester is made up of ~30g of calcium. 99 per cent of it is actively transported one-way from the mother to the fetus via the placenta at the beginning of week 12 gestation-peaking at week 36.

Fetal calcium levels suggest that ionized calcium is transferred from mother to fetus at a rate of 50 mg/day at 20 weeks of gestation to a maximum of 330 mg/day at 35 weeks of gestation—which is why it is so crucial for mothers to get at least 1,000mg of extra calcium daily while pregnant. This not only ensures the fetus is getting enough calcium, but it also prevents maternal osteoporosis.

It varies according to a child’s age-kids need more calcium as they get older to support their growing bones. The American Association of Pediatrics (AAP) recommends:

• Babies under 6 months : 200 mg per day
• Babies 6-11 months : 260 mg per day
• Children 1-3 years of age : 700 mg per day
• Children 4-8 years of age : 1000 mg per day
• Children 9-18 years of age : 1300 mg per day

While it is crucial for all stages of human growth and development from fetus to adulthood-the calcium requirement is at its highest point between the ages of 9 and 18, the pubertal stage, as there are growth spurts.

The best sources are dairy foods such as milk, cheese, and yogurt. For those who are lactose intolerant, dark, leafy green vegetables contain calcium as well, albeit in much smaller amounts. Other alternatives include tofu, calcium-fortified soy drinks, broccoli, Chinese cabbage, legumes, almonds, and sesame seeds.

It is important to note that calcium and Vitamin D go hand-in-hand as the latter helps the body to absorb calcium. Without it, calcium is unable to go towards building strong bones. Therefore, a child requires approximately 600 international units (IU) of Vitamin D per day.

Meanwhile, breastfed babies would need a Vitamin D supplement-starting soon after birth-as breast milk is low in Vitamin D. For formula-fed babies, most infant formulas would have added Vitamin D.

1. Calcium does not work alone. A healthy diet; weight-bearing physical activity; and Vitamin D are also crucial for developing strong bones.
2. Regular weight-bearing activities such as walking, running, jumping; and playing sports (such as football or basketball) can help build strong bones.
3. Remember to supplement your child with Vitamin D to ensure efficient calcium metabolism.

This article was contributed by Dr Goh Chun Hwee, Consultant Paediatrician at Pantai Hospital Ampang. To know more about where and when to see Dr Goh Chun Hwee at his clinic, click here.