Calcium and vitamin D supplements fail to increase BMD or prevent fractures in premenopausal women

A new study found that isolated or combined use of calcium and vitamin D supplementation did not improve bone mineral density or prevent fractures in the total hip or lumbar spine of premenopausal women. The study results were published in the journal Cochrane database of systematic reviews. 

Osteoporosis is a major public health concern worldwide, where bones are fragile due to low bone density and impaired bone quality resulting in fractures that lead to higher morbidity and reduced quality of life. Preventive measures like exercise and a healthy diet are among the lifestyle factors that can help prevent the disease, the latter including intake of key micronutrients for bone, such as calcium and vitamin D. As there is uncertainty on whether calcium and vitamin D supplementation improves bone mineral density (BMD) in premenopausal women, researchers conducted a study to evaluate the benefits and harms of calcium and vitamin D supplementation, alone or in combination, to increase the BMD, reduce fractures, and report the potential adverse events in healthy premenopausal women compared to placebo. 

Using standard Cochrane methods, randomized controlled trials in healthy premenopausal women with or without calcium or vitamin D deficiency that compared supplementation of calcium or vitamin D (or both) at any dose and by any route of administration versus placebo for at least three months were taken into the study. Vitamin D could have been administered as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2). The main outcomes included total hip bone mineral density (BMD), lumbar spine BMD, quality of life, new symptomatic vertebral fractures, new symptomatic non‐vertebral fractures, withdrawals due to adverse events, serious adverse events, all reported adverse events and additional withdrawals for any reason. 

Key findings: 

• There were seven RCTs with 941 participants, of whom 138 were randomized to calcium supplementation, 110 to vitamin D supplementation, 271 to vitamin D plus calcium supplementation, and 422 to placebo.
• Mean age ranged from 18.1 to 42.1 years.
• Studies reported results for total hip or lumbar spine BMD (or both) and withdrawals for various reasons, but none reported fractures or withdrawals for adverse events or serious adverse events.
• Results for the reported outcomes are presented for calcium versus placebo, vitamin D versus placebo, and calcium plus vitamin D versus placebo.
• No clinical difference in outcomes was found in all comparisons, and the certainty of the evidence was moderate to low.
• Most studies were at risk of selection, performance, detection, and reporting biases. 

Thus, without any necessity for further studies in premenopausal women, the present Cochrane analysis revealed that the isolated or combined use of calcium and vitamin D supplementation did not have any beneficial effect. 

Further reading: 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 of Systematic Reviews 2023, Issue 1. Art. No.: CD012664. DOI: 10.1002/14651858.CD012664.pub2. Accessed 08 February 2023.