A study in the American Journal of Nutrition (August 2014) looked at the effect of calcium intake in diabetics and their risk to develop heart disease; not only did they fail to show a negative effect of calcium supplementation, but instead detected a reduction in all-cause mortality over 9.4 years in the 720 women who participated in the study.
These women were part of the Diabetes Heart Study. At the time of enrolment food questionnaires were administered that determined the amount of calcium intake. Calcium supplements were also noticed and factored in. Baseline atherosclerotic plaque of the coronary arteries was determined by computerized tomography. The investigators could not find any association between calcified plaques on the CT scans and calcium consumption by food intake or supplements. The authors expected that maybe calcium intake would cause greater all-cause mortality over the follow-up period. Instead they found the opposite to be true: calcium supplementation lead to a 38% lower risk from all-cause mortality for every 500 mg per day increase of calcium supplementation in this study. The lead author, Laura M. Raffield and associates said: “In this study we did not observe any negative cardiovascular impacts of differing calcium intakes from diet and supplements in contrast to some previous reports”.
When it comes to the details of calcium metabolism, it is important to note that there is interplay between three components: calcium, vitamin K2 and vitamin D3. Vitamin D3 is necessary to absorb calcium from the gut and help with uptake of calcium into the bone together with vitamin K2. Vitamin K2 is necessary to remove calcium from tissues and from the arterial walls and is needed to bind calcium to the bone. I have explained this in detail in this blog.
It is very obvious that calcium alone is not beneficial. There are other players needed in the team. With enough vitamin K2 and vitamin D3 around, calcium will not cause any harm and will actually show the beneficial effects this study has shown. Remove vitamin K2 and D3 and calcium will have harmful effects on the heart vessels as mentioned in other studies. The person affected with this would also develop osteoporosis.
More information about osteoporosis: https://nethealthbook.com/arthritis/osteoporosis/
Am. J. Clin. Nutr. 1014, Aug.6