Numerous studies have pointed to an association between too much calcium and prostate cancer risk. Several factors around this issue need to be explored, such as what constitutes too much calcium, the sources of the calcium, and the role of calcium deposits in the prostate.
Too much calcium and prostate cancer
Numerous studies point to an association between high calcium intake and prostate cancer. What constitutes high intake? In a 24-year follow-up study appearing in the American Journal of Clinical Nutrition, the authors noted that men who consumed more than 2,000 mg daily of calcium had a greater risk of prostate cancer and deadly, high-grade cancers.
More specifically, high intake of calcium was associated with a greater risk of high-grade and advanced disease 12 to 16 years after exposure. Calcium was not the only culprit, however. They also reported that high intake of phosphorus also was associated with an increased risk of high-grade and advanced disease zero to eight years after exposure.
In other research, the authors reported that taking more than 1,500 mg daily was associated with a greater risk of advanced and deadly prostate cancer. Men with a Gleason score of 7 or higher also had a higher risk.
In a large meta-analysis and review that looked at data from the Continuous Update Project, intake of dairy products and calcium were examined in relation to prostate cancer risk. The authors evaluated 32 studies and found that intake of total dairy products, total milk, low-fat milk, cheese, and dietary calcium were associated with an increased risk of prostate cancer. They also noted that calcium supplements were associated with a greater risk of deadly prostate cancer.
What about the source of calcium
The most common ways men ingest calcium is through dairy foods and supplements. An association between milk and dairy products and an increased risk of prostate cancer has already been shown in numerous studies.
One question that arises is the independent impact of other components found in dairy foods, such as protein, vitamin D, phosphorus, potassium, magnesium, and vitamin A. However, studies that have separated these effects generally have noted that calcium “may be the predominant player underlying positive associations with prostate cancer.”
When it comes to calcium supplements, the verdict is uncertain.
In a study of the impact of calcium and dairy foods on prostate cancer risk among more than 293,000 men followed up for six years, the investigators found no association between total and supplemental calcium intake and all prostate cancer and nonadvanced disease. However, they did note a relationship between total calcium intake and advanced and fatal prostate cancer.
Calcium deposits
Calcium deposits, or calcification, can appear throughout the body because the mineral is found in every cell, travels through the bloodstream, and reaches all of your body tissues, organs, and blood vessels. A calcium buildup can appear in the breast as well as in your arteries, muscles, brain, joints, bladder, and prostate.
Such calcium deposits can disrupt your body’s normal processes in the prostate, but that does not necessarily mean such an accumulation is associated with prostate cancer. That said, as noted above, excess calcium has been associated with an increased risk of prostate cancer.
If your doctor discovers calcium deposits in your prostate during a rectal ultrasound or pelvic x-ray, other factors such as an elevated PSA or other prostate abnormalities should be checked to determine whether a biopsy or other diagnostic techniques should be pursued.
Bottom line
The relationship between prostate cancer risk and mortality and calcium intake requires more investigation. It appears that lower rather than higher intake of calcium is better when it comes to prostate health, but men also need to maintain adequate calcium intake (along with vitamin D and other nutrients) to preserve and support bone health. Men should discuss the topic of too much calcium and prostate cancer risk with trusted medical professionals, especially if they are at increased risk or already have the disease.
References
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Gao X et al. Prospective studies of dairy product and calcium intakes and prostate cancer risk: a meta-analysis. Journal of the National Cancer Institute 2005; 97:1768–77.
Giovannucci E et al. A prospective study of calcium intake and incident and fatal prostate cancer. Cancer Epidemiology Biomarkers Preview 2006; 15:203–10.
Giovannucci E et al. Risk factors for prostate cancer incidence and progression in the Health Professionals Follow-up Study. International Journal of Cancer 2007; 121:1571–78.
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Park Y et al. Calcium, dairy foods, and risk of incident and fatal prostate cancer: the NIH-AARP Diet and Health Study. American Journal of Epidemiology 2007; 166:1270–9.
Rahmati S et al. Total calcium (dietary and supplementary) intake and prostate cancer: a systematic review and meta-analysis. Asian Pacific Journal of Cancer Prevention 2018 Jun 25; 19(6): 1449-56
Rohrmann S et al. Meat and dairy consumption and subsequent risk of prostate cancer in a US cohort study. Cancer Causes Control 2007; 18:41–50.
Wilson KM et al. Calcium and phosphorus intake and prostate cancer risk: a 24-y follow-up study. American Journal of Clinical Nutrition 2015 Jan; 101(1): 173-83