Calcium

Do calcium supplements cause kidney stones?

Updated 4 Nov 2026

Short answer

They may raise the risk slightly, and the evidence is mixed. In the largest trial, 36,282 women took 1,000 mg of calcium with 400 IU of vitamin D or a placebo for 7 years, and kidney stones were 17% more common with the supplement.[1] The US upper limit is based on this finding.[2]

A 2022 evidence report for the US Preventive Services Task Force also found limited evidence of a higher risk.[3] Other reviews did not. A review of 10 studies in more than 8,000 people with osteoporosis found no significant increase.[4] A review of 11 trials in 51,419 adults found no link,[2] and a 2012 opinion of EFSA, the EU food safety authority, found no established link.[5]

A diet low in calcium did not protect better. A trial in 120 men with repeated calcium oxalate stones and high urine calcium compared two diets. One had normal calcium with less animal protein and salt, and the other was low in calcium. Over 5 years, 12 men on the first diet and 23 on the second had new stones.[6]

People who have had kidney stones should ask a doctor or pharmacist before they take calcium supplements.[1]

Sources (6)

  1. Calcium plus vitamin D supplementation and the risk of fractures. Jackson RD, LaCroix AZ, Gass M, Wallace RB, Robbins J, Lewis CE, et al. N Engl J Med, 2006. PMID 16481635
  2. Calcium: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements. ods.od.nih.gov
  3. Vitamin and Mineral Supplements for the Primary Prevention of Cardiovascular Disease and Cancer: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. O'Connor EA, Evans CV, Ivlev I, Rushkin MC, Thomas RG, Martin A, et al. JAMA, 2022. PMID 35727272
  4. Calcium supplementation and kidney stone risk in osteoporosis: a systematic literature review. Candelas G, Martinez-Lopez JA, Rosario MP, Carmona L, Loza E Clin Exp Rheumatol, 2012. PMID 23137489
  5. Scientific Opinion on the Tolerable Upper Intake Level of calcium. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) European Food Safety Authority, 2012. efsa.onlinelibrary.wiley.com
  6. Comparison of two diets for the prevention of recurrent stones in idiopathic hypercalciuria. Borghi L, Schianchi T, Meschi T, Guerra A, Allegri F, Maggiore U, et al. N Engl J Med, 2002. PMID 11784873

More about calcium

What is calcium?Which foods contain calcium?Does calcium need vitamin D to work?How much calcium can the body absorb at one time?What is calcium used for?What happens if you do not get enough calcium?

For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.