Calcium Nutrient Summary

Written by Olivia Farrow, RD, MHSc

Reviewed by Krista Kolodziejzyk, RD, MPH, MBA

This article will explore the multiple roles of calcium in the body and considerations for supplementation.

Calcium is a mineral that has long been associated with strong bones and teeth (1). However, its role in the human body goes far beyond that. As health professionals, understanding the intricacies of calcium can help us in supporting our clients and patients to maintain optimal health. 

For a full evidence summary on calcium and a food sources list join Dietitian Success Center’s membership which includes access to comprehensive yet simplified reference guides and client handouts for many nutrients, including calcium. 

The Role of Calcium in the Body

Calcium is not merely a building block for bones; it is a versatile mineral that participates in several essential bodily functions. Its primary roles include:

      • Maintaining the integrity and strength of bones and teeth (1).

      • Muscle contraction and relaxation, which is needed for activities ranging from walking to heartbeat regulation (1).

      • Transmitting nerve signals throughout the body, ensuring proper communication between nerve cells (1).

      • Secretion of various hormones in the body, contributing to overall hormonal balance (1).

    Recommended Daily Intake

    Recommended dietary allowances (RDAs) have been established for calcium (1):

    Age/Stage RDA UL
      Male Female  
    0-6 months 200 mg (AI) 1000 mg
    6-12 months 260 mg (AI) 1500 mg
    1-3 years 700 mg 2500 mg
    4-8 years 1000 mg 2500 mg
    9-18 years 1300 mg 3000 mg
    19-50 years 1000 mg 2500 mg
    51-70 years 1000 mg 1200 mg 2000 mg
    70+ years 1200 mg 2000 mg
    Pregnancy & Lactation ≤18 years 1300 mg 3000 mg
    Pregnancy & Lactation >18 years 1000 mg 2500 mg

    Sources of Dietary Calcium

    In the United States and Canada, dairy products like milk, yogurt, and cheese are the primary sources of dietary calcium for many people (1,2). However, there is a wide range of other food sources that contribute to calcium intake, which can be found in DSC’s Food Sources of Nutrients Compilation.


    Calcium Deficiency

    Calcium deficiency can have serious consequences, particularly on bone health. In children, it can lead to rickets, while adults may suffer from osteoporosis (loss of bone density) and osteomalacia (bone softening) (2). Factors contributing to calcium deficiency include vitamin D deficiency, critical illness (ICU patients), certain medications, and low dietary calcium intake (2). Postmenopausal women are also at increased risk due to reduced calcium absorption (1,2).


    Calcium Supplementation

    Health professionals often face questions about the necessity of calcium supplementation. 

    Here’s a brief overview of its role in various health conditions:

        • Bone Health: Calcium supplementation’s impact on bone health is a topic of ongoing debate. While some observational studies suggest benefits, clinical trials have yielded mixed results (3,4,5,6). More research is needed to determine its effectiveness, in supporting optimal bone health especially in different age groups.

        • Cardiovascular Disease: Calcium can affect lipid absorption, but its role in cardiovascular health remains uncertain. Studies have produced conflicting results, with some indicating potential benefits and others suggesting increased cardiovascular risk (7,8,9,10,11).

        • Cancer: Research on the link between calcium intake and cancer risk is inconclusive (2,12). While some evidence suggests a reduced risk of colorectal cancer, more comprehensive studies are required (13,14,15,16).

        • Preeclampsia: Calcium supplementation may have a role in reducing the risk of preeclampsia (high blood pressure in pregnancy), but the evidence is not conclusive (17,18). 

        • Premenstrual Syndrome (PMS): Calcium intake, both dietary and through supplements, may help manage symptoms of PMS and premenstrual dysphoric disorder (PMDD; a more severe form of PMS) (19,20,21,22).


      Considerations for Calcium Supplements

      When recommending calcium supplements, consider the following:

          • Many calcium-rich foods also provide other essential nutrients, making dietary sources preferable when possible (2).

          • Calcium supplements should be considered when dietary intake is insufficient (2).

          • Dosing should be spaced in 500 mg doses for optimal absorption (23).

          • For individuals taking antacids that contain calcium (TUMS®, Rolaids®), consider total daily intake alongside additional supplements or fortified foods.

          • Calcium may interact with some medications and other nutrient supplements, such as iron, so timing when taking the supplement should be considered (2).

          • Although calcium carbonate is the most common supplementation form, alternatives such as calcium-lactate and aspartate, may be better tolerated (23).


        Key Takeaways

            • Calcium plays many roles in the body, most famously in the health of bones and teeth.

            • Dairy products are the most commonly consumed dietary sources of calcium.

            • Dietary sources of calcium contribute other important nutrients alongside and should be considered when possible as an alternative to supplementation.

            • Calcium supplements may play a role in the management of several health conditions, including, bone health, cardiovascular disease, cancer, preeclampsia and PMS. 

          For a more thorough overview of the evidence on Calcium, check out DSC’s Calcium Evidence Summary

          Disclaimer: the information provided in all written materials is for educational purposes only and is not to be used as medical advice or to diagnose or treat a medical disease. It is strictly for informational purposes and is general in nature. Dietitian Success Center Inc. is not responsible and cannot be held liable for any actions or inactions taken related to the information provided. Consult with your local medical provider before implementing any dietary changes. It is hereby understood that the information provided does not replace medical advice provided by your healthcare provider.


            1. National Academies of Sciences, Engineering, and Medicine. 2011. Dietary Reference Intakes for Calcium and Vitamin D. Washington, DC: The National Academies Press.

            2. National Institutes of Health. “Calcium – Health Professionals Fact Sheet”. Updated 2022. Available from

            3. Méndez-Sánchez L, Clark P, Winzenberg TM, Tugwell P, Correa-Burrows P, Costello R. Calcium and vitamin D for increasing bone mineral density in premenopausal women. Cochrane Database Syst Rev. 2023 Jan 27;1(1):CD012664. doi: 10.1002/14651858.CD012664.pub2. PMID: 36705288; PMCID: PMC9881395.

            4. Crandall CJ, Aragaki AK, LeBoff MS, Li W, Wactawski-Wende J, Cauley JA, Margolis KL, Manson JE. Calcium plus vitamin D supplementation and height loss: findings from the Women’s Health Initiative Calcium and Vitamin D clinical trial. Menopause. 2016 Dec;23(12):1277-1286. doi: 10.1097/GME.0000000000000704. PMID: 27483038; PMCID: PMC5118123.

            5. Liu C , Kuang X , Li K , Guo X , Deng Q , Li D . Effects of combined calcium and vitamin D supplementation on osteoporosis in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials. Food Funct. 2020 Dec 1;11(12):10817-10827. doi: 10.1039/d0fo00787k. Epub 2020 Nov 25. PMID: 33237064.

            6. Weaver CM, Alexander DD, Boushey CJ, Dawson-Hughes B, Lappe JM, LeBoff MS, Liu S, Looker AC, Wallace TC, Wang DD. Calcium plus vitamin D supplementation and risk of fractures: an updated meta-analysis from the National Osteoporosis Foundation. Osteoporos Int. 2016 Jan;27(1):367-76. doi: 10.1007/s00198-015-3386-5. Epub 2015 Oct 28. 

            7. Cormick G, Ciapponi A, Cafferata ML, Belizán JM. Calcium supplementation for prevention of primary hypertension. Cochrane Database Syst Rev. 2015 Jun 30;2015(6):CD010037. doi: 10.1002/14651858.CD010037.pub2. Update in: Cochrane Database Syst Rev. 2021 Aug 10;8:CD010037. PMID: 26126003; PMCID: PMC6486289.

            8. Chen C, Ge S, Li S, Wu L, Liu T, Li C. The Effects of Dietary Calcium Supplements Alone or With Vitamin D on Cholesterol Metabolism: A Meta-Analysis of Randomized Controlled Trials. J Cardiovasc Nurs. 2017 Sep/Oct;32(5):496-506. doi: 10.1097/JCN.0000000000000379. PMID: 27870724.

            9. Myung SK, Kim HB, Lee YJ, Choi YJ, Oh SW. Calcium Supplements and Risk of Cardiovascular Disease: A Meta-Analysis of Clinical Trials. Nutrients. 2021 Jan 26;13(2):368. doi: 10.3390/nu13020368. PMID: 33530332; PMCID: PMC7910980.

            10. Yang B, Campbell PT, Gapstur SM, Jacobs EJ, Bostick RM, Fedirko V, Flanders WD, McCullough ML. Calcium intake and mortality from all causes, cancer, and cardiovascular disease: the Cancer Prevention Study II Nutrition Cohort. Am J Clin Nutr. 2016 Mar;103(3):886-94. doi: 10.3945/ajcn.115.117994. Epub 2016 Feb 10. PMID: 26864361.

            11. Kopecky SL, Bauer DC, Gulati M, Nieves JW, Singer AJ, Toth PP, Underberg JA, Wallace TC, Weaver CM. Lack of Evidence Linking Calcium With or Without Vitamin D Supplementation to Cardiovascular Disease in Generally Healthy Adults: A Clinical Guideline From the National Osteoporosis Foundation and the American Society for Preventive Cardiology. Ann Intern Med. 2016 Dec 20;165(12):867-868. doi: 10.7326/M16-1743. Epub 2016 Oct 25. PMID: 27776362.

            12. Linus Pauling Institute. “Calcium” (2001-2003) Available from This link leads to a website provided by the Linus Pauling Institute at Oregon State University. Dietitian Success Center is not affiliated or endorsed by the Linus Pauling Institute or Oregon State University.

            13. Barrubés L, Babio N, Becerra-Tomás N, Rosique-Esteban N, Salas-Salvadó J. Association Between Dairy Product Consumption and Colorectal Cancer Risk in Adults: A Systematic Review and Meta-Analysis of Epidemiologic Studies. Adv Nutr. 2019 May 1;10(suppl_2):S190-S211. doi: 10.1093/advances/nmy114. 

            14. Bristow SM, Bolland MJ, MacLennan GS, Avenell A, Grey A, Gamble GD, Reid IR. Calcium supplements and cancer risk: a meta-analysis of randomised controlled trials. Br J Nutr. 2013 Oct;110(8):1384-93. doi: 10.1017/S0007114513001050. Epub 2013 Apr 19. PMID: 23601861.

            15. Torfadottir JE, Steingrimsdottir L, Mucci L, Aspelund T, Kasperzyk JL, Olafsson O, Fall K, Tryggvadottir L, Harris TB, Launer L, Jonsson E, Tulinius H, Stampfer M, Adami HO, Gudnason V, Valdimarsdottir UA. Milk intake in early life and risk of advanced prostate cancer. Am J Epidemiol. 2012 Jan 15;175(2):144-53. doi: 10.1093/aje/kwr289. Epub 2011 Dec 20. PMID: 22190107; PMCID: PMC3249408.

            16. Huncharek M, Muscat J, Kupelnick B. Dairy products, dietary calcium and vitamin D intake as risk factors for prostate cancer: a meta-analysis of 26,769 cases from 45 observational studies. Nutr Cancer. 2008;60(4):421-41. doi: 10.1080/01635580801911779. PMID: 18584476.

            17. Hofmeyr GJ, Lawrie TA, Atallah ÁN, Torloni MR. Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems. Cochrane Database Syst Rev. 2018 Oct 1;10(10):CD001059. doi: 10.1002/14651858.CD001059.pub5. PMID: 30277579; PMCID: PMC6517256.

            18. Hofmeyr GJ, Manyame S, Medley N, Williams MJ. Calcium supplementation commencing before or early in pregnancy, for preventing hypertensive disorders of pregnancy. Cochrane Database Syst Rev. 2019 Sep 16;9(9):CD011192. doi: 10.1002/14651858.CD011192.pub3. PMID: 31523806; PMCID: PMC6745517.

            19. Bertone-Johnson ER, Hankinson SE, Bendich A, Johnson SR, Willett WC, Manson JE. Calcium and vitamin D intake and risk of incident premenstrual syndrome. Arch Intern Med. 2005 Jun 13;165(11):1246-52. doi: 10.1001/archinte.165.11.1246. PMID: 15956003.

            20. Thys-Jacobs S, Starkey P, Bernstein D, Tian J. Calcium carbonate and the premenstrual syndrome: effects on premenstrual and menstrual symptoms. Premenstrual Syndrome Study Group. Am J Obstet Gynecol. 1998 Aug;179(2):444-52. doi: 10.1016/s0002-9378(98)70377-1. PMID: 9731851.

            21. Shobeiri F, Araste FE, Ebrahimi R, Jenabi E, Nazari M. Effect of calcium on premenstrual syndrome: A double-blind randomized clinical trial. Obstet Gynecol Sci. 2017 Jan;60(1):100-105. doi: 10.5468/ogs.2017.60.1.100. Epub 2017 Jan 15. PMID: 28217679; PMCID: PMC5313351.

            22. Abdi F, Ozgoli G, Rahnemaie FS. A systematic review of the role of vitamin D and calcium in premenstrual syndrome. Obstet Gynecol Sci. 2019 Mar;62(2):73-86. doi: 10.5468/ogs.2019.62.2.73. Epub 2019 Feb 25. Erratum in: Obstet Gynecol Sci. 2020 Mar;63(2):213. PMID: 30918875; PMCID: PMC6422848.

            23. Raymond, J., Morrow, K. 2021. “Nutritional Facts on Calcium”. In Krause and Mahan’s Food & The Nutrition Care Process: 15th Edition. Page 1117; Appendix 39. Elsevier, Inc.

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