Controversy Over Calcium- Avoid the Risks. Calcium is necessary to keep our bones strong and it also plays a role in nerve conduction, and muscle contraction. It moves blood throughout your blood vessels. Therefore, acts as a signaling molecule to release hormones and enzymes and plays a role in blood clotting by regulating platelet activation. The controversy arises over what is a “sufficient amount” and whether someone should supplement with calcium to prevent bone fractures.

However, osteoporosis is one of the leading causes of disability in older people. Furthermore, calcium supplements have been recommended to prevent bone loss, yet some other studies contradict that assessment. All studies have their flaws, and we need to make sense of the recommendations and individualize them to a person’s specific conditions and risk factors.

display of foods containing calciumHow much is enough?

Different organizations have different recommendations:

  • National Institutes of Health recommends 1,000 mg for women under the age of 50 and 1,200 mg for women over 50,
  • World Health Organization recommends 500 mg
  • United Kingdom recommends700 mg
  • Walter Willett, chair of the Department of Nutrition at the Harvard T.H. Chan School of Public Health says: “The recommendation was based on calcium balance studies that lasted just a few weeks. In fact, calcium balance is determined over the course of years.” Moreover, there wasn’t any evidence that consuming that much calcium actually prevented fractures.

Too much calcium can pose risks!

  • Dementia
  • Stroke
  • Kidney Stones
  • Heart Disease

Let’s dissect some of the studies so we can feel more comfortable with our decisions.

Dementia and Stroke

An observational study showed that only women with cerebrovascular disease were at risk. For instance, no increased risk was found in women without a history of stroke or white matter lesions.

  • Women who were treated with calcium supplements were twice as likely to develop dementia than women who did not take supplements. But when the researchers further analyzed the data, they found that the increased risk was only among women with cerebrovascular disease.
  • Women with a history of stroke who took supplements had a nearly seven times increased risk of developing dementia than women with a history of stroke who did not take calcium supplements.
  • Women with white matter lesions who took supplements were three times as likely to develop dementia as women who had white matter lesions and did not take supplements.
  • Women without a history of stroke or women without white matter lesions had no increased risk when taking calcium supplements.

Kidney Stones

Moreover, high doses of dietary calcium may be beneficial to kidney health and prevent kidney stones.

  • Excess amounts of calcium from supplements are eliminated in the urine in increased amounts and may promote kidney stone formation
  • Vitamin D supplementation may prevent the risk of stone formation because of decreased calcium in the urine.


In a meta-analysis of cardiovascular data that was unpublished in randomized control trials the results showed:

  • Calcium supplements without Vitamin D increased the risk of heart attacks by 27–31%.
  • The use of calcium supplements also increased the risk of stroke and mortality, but this risk was not statistically significant.
  • Pooling results from 4 trials researchers found that calcium combined with Vitamin D increased the risk of heart attack by 21% and stroke by 20%


  • There has not been a problem consuming calcium from your diet.
  • It is easy to get the newer recommendation of 500-700 mg of calcium from your diet
  • It seems Vitamin D may be helpful to prevent kidney stones as it increases calcium absorption and decreases its loss in the urine.
  • If you have cardiovascular or stroke risk, it is best to avoid calcium.
  • Calcium intake may be beneficial in post-menopausal women who are institutionalized and do not get much sunlight.
  • Calcium supplements should be recommended for people who are not getting enough calcium in their diets.
  • US Preventive Services Task Force recommended against calcium supplements for the primary prevention of fractures in noninstitutionalized postmenopausal women.
  • After several decades of research, investigators have come to the conclusion that a calcium-vitamin D combination supplement does not decrease the risk of hip fractures in postmenopausal women, implicating that the minor bone density benefits associated with calcium supplementation do not outweigh the potential health risks

The bottom line is that dietary calcium is more beneficial for health than calcium supplements and that it is also easier to absorb. One must weight each person’s risk versus benefit in deciding whether or not to supplement with calcium. Seek the advice of a functional medicine doctor to help with a safe, effective, and natural solution to prevent osteoporosis.