The study, published in the British Medial Journal and reported by NutraIngredients here, warned that the risks of heart problems outweigh the potential benefits of calcium supplementation, with the lead researcher Professor Ian Reid saying that the results suggest that the indiscriminate use of calcium supplements ‘should be abandoned’.
However, leading industry figures have come out to counter-slam the results of the study, questioning the “flawed” methodology and statistical interpretation of the meta-analysis.
John Hathcock, senior vice president of scientific and international affairs at the Council for Responsible Nutrition (CRN) told NutraIngredients that he “wouldn’t put a lot of weight” on the conclusions, adding that he believed the methodology of the study “raises more questions than it provides answers.”
Rich history
Last year, Professor Reid and his research team published a study (reported here) suggesting that regular calcium supplementation, taken to reduce the risk of osteoporosis may in-fact cause more heart attacks than the number of fractures they prevent.
The research team then re-analysed the data from this study, but this time included data of three new trials which looked at the effects of calcium plus vitamin D; something that the previous study received criticism for omitting last time around.
This new meta-analysis, with data from 29000 people, reported similar findings, suggesting that the risk of heart problems outweigh the potential benefits of calcium supplementation.
Flawed analysis?
“We saw this same flawed analysis last year with some slight changes, but we’re still looking at a meta-analysis of other studies […] This latest analysis does not present compelling evidence against calcium and vitamin D, and in fact, there are many more studies touting the beneficial effects for both,” said Dr. Cara Welch, vice president of scientific and regulatory affairs for the Natural Products Association (NPA).
Welch added that she hoped that individuals who use calcium supplements for bone health will continue supplementation “and not be swayed by this flawed analysis.
“We have seen over and over the argument that Americans can get all the nutrients they need from a balanced diet. But the fact is, most don’t,” she argued.
Hathcock of the CRN added to this sentiment by questioning the way the statictics have been interpreted in the new analysis:
“Instead of considering these findings a coincidence or a statistical abnormality as there are with many analyses of large pools of data with many variables, the authors instead suggest that the abrupt change in blood calcium levels after supplementation is what causes the effect … It seems more likely that findings are a procedural or statistical anomaly,” said Hathcock
However, Prof. Reid responded to the claims that the studies methods were flawed, telling NutraIngredients that the methodology and statistical rigour of the studies findings have been independently tested, and commended, on two occasions during the research’s review and publication process.
High stakes
Reid said that he knew the research findings would be “a high stake statement,” adding that the “net losers would of course be industry […] because it has substantial impact on all the people who take calcium and also on all the people who make it.”
“For that reason we have been expecting very close scrutiny and I think we have been particularly meticulous in the way we carried out this analysis so that any scrutiny doesn’t hold problems for us,” he said.
Further consideration
Harry Rice, V.P., Regulatory & Scientific Affairs for the United Natural Products Alliance (UNPA), told NutraIngredients that the he believes that the study provides “far too little evidence” to dictate public health policy.
“The reported results are interesting and there’s little doubt in my mind that the association between cardiovascular events and calcium supplementation with or without vitamin D warrants further consideration via future research,” said Rice.
Cathy Ross, senior cardiac nurse at the British Heart Foundation added to the calls for further investigation:
“The study showed there was a modest increase in heart attack or stroke risk but that’s not the same as saying calcium supplements with vitamin D cause heart attacks and strokes, only that there was an increased risk … It’s very important further studies are carried out to determine the effects of calcium supplements on heart health,” said Ross.
“There is still not enough evidence to confirm the association between calcium supplements and cardiovascular risk,” she added.