Quick answer
NIH gives 1,300 mg of calcium a day for ages 9 to 18 and sets the upper limit at 2,500 mg for ages 1 to 8 and 3,000 mg for 9 to 18. A Cochrane review of 19 trials in 2,859 healthy children reported that adverse events were infrequent and minor.1,2
Key facts
- NIH gives 700 mg of calcium a day at ages 1 to 3, 1,000 mg at 4 to 8 and 1,300 mg at 9 to 18.1,3
- The upper limits are 2,500 mg at ages 1 to 8 and 3,000 mg at 9 to 18, from food, drinks and supplements.1,3
- A Cochrane review of 19 trials in 2,859 children reported adverse events as infrequent and minor, and did not back calcium supplements for healthy children as a public health step.2
- NIH says 49% of US children aged 4 to 18 take in less than the estimated average requirement for calcium, and 4% to 8% take a calcium supplement.1
- Calcium carbonate causes gas, bloating and constipation more often than calcium citrate.1,3
How much calcium do children and teens need, and what is the limit?
| Age | Amount NIH gives a day | Upper limit a day |
|---|---|---|
| 1 to 3 years | 700 mg | 2,500 mg |
| 4 to 8 years | 1,000 mg | 2,500 mg |
| 9 to 13 years | 1,300 mg | 3,000 mg |
| 14 to 18 years | 1,300 mg | 3,000 mg |
NIH says the amounts for children and teens are based on intakes linked to bone accumulation. The limits count food, drinks and supplements together. NIH says they rest on observational evidence from the Women's Health Initiative, a study in older women, and that two later systematic reviews found no such association.1
Children aged 9 to 18 need 1,300 mg a day, as do pregnant and breastfeeding teens. Pregnant and breastfeeding women aged 19 and older need 1,000 mg.1,3
What did the Cochrane review of calcium supplements in children report?
The review pooled 19 trials with 2,859 healthy children, 1,367 given calcium and 1,426 given placebo. It reported that adverse events were reported infrequently and were minor. It also found only small differences in bone measures at some sites, and its authors concluded that the results do not back calcium supplements in healthy children as a public health measure, while noting the results cannot be extended to children with medical conditions that affect bone.2
A companion meta-analysis in the BMJ by the same group reached the same conclusion on bone density in healthy children.4
Is calcium citrate or carbonate better tolerated by kids?
NIH says calcium carbonate appears to cause gas, bloating and constipation more often than calcium citrate, and that calcium citrate is less dependent on stomach acid and can be taken without food. NIH describes this mostly in adults, and the sources checked did not compare the forms in children.1,3
Calcium supplements can cause gas, bloating, constipation or a mix of these. Carbonate causes them more often than citrate, especially in older adults with less stomach acid; smaller doses spread through the day, taking it with meals or switching forms can help.1,3
Who should ask a doctor about calcium for a child or teen
- Parents of a child or teen who takes calcium gummies, chews or tablets together with fortified foods, milk and a multivitamin, who should ask the pediatrician to add up the calcium.1
- Parents of a child with kidney stones, kidney disease or a condition that affects bone, since the Cochrane results do not extend to those children.2
- Parents of a child who takes levothyroxine, a quinolone or tetracycline antibiotic, or another medicine that calcium can bind.1
- Parents of a teen with constipation, gas or bloating after starting calcium, who should ask about the amount and the form.1
Questions people ask
Is calcium safe for kids?
NIH sets an upper limit of 2,500 mg a day at ages 1 to 8, and a Cochrane review of 19 trials in healthy children reported adverse events as infrequent and minor. Ask your pediatrician about a supplement.1,2
Is calcium good for teens?
NIH gives 1,300 mg a day for ages 9 to 18 from food and supplements together, and says 49% of US children aged 4 to 18 fall below the estimated average requirement. Ask your doctor before a teen starts a supplement.1
Is calcium carbonate safe for kids?
NIH says carbonate causes gas, bloating and constipation more often than citrate, and the 2,500 mg upper limit for ages 1 to 8 counts all sources. Ask your pediatrician.1
Is calcium citrate good for teens?
NIH says calcium citrate can be taken without food and causes digestive effects less often than carbonate, with an upper limit of 3,000 mg at 9 to 18. Ask your doctor.1
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Sources
- Office of Dietary Supplements, National Institutes of Health. Calcium: Fact Sheet for Health Professionals. Updated June 22, 2026. Opened 2026-10-07.
- Winzenberg TM, Shaw K, Fryer J, Jones G. Calcium supplementation for improving bone mineral density in children. Cochrane Database Syst Rev. 2006;2006(2):CD005119. A Cochrane systematic review of randomized trials. Opened 2026-10-11.
- Office of Dietary Supplements, National Institutes of Health. Calcium: Fact Sheet for Consumers. Updated September 14, 2023. Opened 2026-10-07.
- Winzenberg T, Shaw K, Fryer J, Jones G. Effects of calcium supplementation on bone density in healthy children: meta-analysis of randomised controlled trials. BMJ. 2006;333(7572):775. A meta-analysis of randomised controlled trials. Opened 2026-10-11.
This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.