Calcium with vitamin d supplements
Pro Research Analysisby 
Searched over 200M research papers
Consensus Meter
The Impact of Calcium with Vitamin D Supplements: A Comprehensive Review
Calcium and Vitamin D Supplements for Fracture Prevention
Hip and Total Fracture Risk Reduction
Calcium and vitamin D supplementation has been extensively studied for its potential to reduce fracture risk, particularly in postmenopausal women. A large-scale study involving 36,282 postmenopausal women found that calcium plus vitamin D supplementation resulted in a modest increase in hip bone density by 1.06% compared to placebo. However, the reduction in hip fracture risk was not statistically significant in the intention-to-treat analysis, with a hazard ratio of 0.88. Another meta-analysis supported these findings, showing a 15% reduced risk of total fractures and a 30% reduced risk of hip fractures with calcium and vitamin D supplementation.
Bone Mineral Density Improvements
Further research indicates that combined calcium and vitamin D supplementation significantly increases bone mineral density (BMD) in various parts of the body. A systematic review and meta-analysis found significant improvements in total BMD, lumbar spine BMD, arms BMD, and femoral neck BMD among postmenopausal women. These findings suggest that while the supplements may not drastically reduce fracture risk, they do contribute to overall bone health.
Calcium and Vitamin D Supplements and Cancer Risk
Colorectal Cancer
The relationship between calcium and vitamin D supplementation and colorectal cancer risk has been explored with mixed results. A randomized trial involving 36,282 postmenopausal women found no significant difference in the incidence of colorectal cancer between the supplement and placebo groups over seven years. This null finding may be attributed to the long latency period associated with colorectal cancer development.
General Cancer Risk
Conversely, another study focusing on a broader range of cancers found that calcium and vitamin D supplementation significantly reduced the risk of all types of cancer. The study reported a relative risk reduction of 0.402 for incident cancer in the supplement group compared to placebo. This suggests that while the supplements may not be effective for colorectal cancer specifically, they could have a protective effect against other forms of cancer.
Metabolic and Cardiovascular Effects
Glucose Metabolism and Lipid Profiles
Calcium and vitamin D supplementation has also been shown to positively affect glucose metabolism and lipid profiles, particularly in specific populations. In overweight and obese women with polycystic ovary syndrome (PCOS), supplementation led to decreased serum insulin levels, improved insulin sensitivity, and reduced serum triglycerides and VLDL-cholesterol levels. Additionally, in a weight-loss intervention study, calcium and vitamin D supplementation enhanced the beneficial effects of weight loss on lipid profiles, including significant reductions in LDL cholesterol and improvements in HDL cholesterol.
Cardiovascular Events
The impact of calcium and vitamin D supplementation on cardiovascular health remains controversial. A study from the Women's Health Initiative found no significant increase or decrease in the risk of coronary or cerebrovascular events among women taking the supplements over seven years. This suggests that while the supplements may offer some metabolic benefits, they do not significantly affect cardiovascular risk.
Conclusion
Calcium and vitamin D supplementation offers several health benefits, including modest improvements in bone density and potential reductions in overall cancer risk. However, its effectiveness in significantly reducing fracture risk, particularly hip fractures, remains limited. Additionally, while the supplements can improve metabolic health in specific populations, their impact on cardiovascular events appears neutral. These findings highlight the importance of targeted supplementation and the need for further research to fully understand the long-term health implications of calcium and vitamin D intake.
Sources and full results
Most relevant research papers on this topic