Nutritional science for mind health products
DSM Nutritional Products
The new data, published in the British Medical Journal, suggests that calcium supplements – when taken with, or without vitamin D – may increase the risk of heart attack by 25 per cent, and the risk of stroke by 15 per cent. The new findings back up the results of an earlier meta-analysis that suggested calcium supplementation could have more risks than benefits .
Professor Ian Reid, senior author of the study, told NutraIngredients that the new data provides “a significant body of evidence that says there is a concern.”
“When we do the calculations from these 29,000 people, we find that for every thousand people we give calcium to for five years, we cause six heart attacks and we prevent three fractures,” said Reid.
“The message from last years study, to this years study is very consistent, and that is that it’s not a very effective way of preventing fractures, and it probably does carry a significant risk,” he warned.
Previous research
Last year, Professor Reid and his researcher team published a study suggesting that regularly supplementation with calcium to reduce the risk of osteoporosis may cause more heart attacks than the number of fractures they prevent.
The previous study (reported here ) looked at calcium supplementation alone, however many people take calcium combined with vitamin D, so Reid and his team then set out to see if their findings held true when this was taken into account.
Study details
Prof. Reid said that the new research was “not so much a re-analysis”, but a new study, which includes a re-analysis.
“What we have done is now found three studies which have calcium plus vitamin D as the intervention … that’s another 17,000 new people in which we looked at the incidence of heart attacks and strokes,” he explained
The results of studying these 17,000 people showed “exactly the same increase in risk from this as we found before” said Reid. “So then we went ahead and combined this data with the data from last year’s meta-analysis of 12,000 people to give us a total meta-analysis of 29,000 people,”
From this overall data, the researchers found a 25 per cent increase in the risk of heart attack, and a 15 per cent increase in the risk of stroke.
“Those effects are much the same as we found last year in terms of the risk size, but now because we have a much larger pool of people, the differences in the data have much higher statistical significance,” said Reid.
“We have a very consistent pattern … you find that in the major studies heart attack risk is very consistent, irrespective of whether or not they are taking vitamin D with the calcium,” concluded Reid.
Industry action
The research team are now investigating the mechanisms behind the effects of calcium supplementation to try and understand why taking supplements may pose a risk to heart health, whilst consuming calcium rich food does not.
Reid told NutraIngredients that finding the mechanisms behind the potential increased risk opens up the possibility of designing calcium supplements that are safer to use.
He confirmed that they are currently working with industry, “to look at ways or means of creating a safer way to deliver calcium to people,” adding that research team is happy to work more with industry “to look into these issues and try to come up with solutions.”
Prof. Reid warned that supplement manufacturers must pay attention to the risks as well as the benefits of calcium supplementation, adding that ignoring or dismissing the issue is not a suitable answer.
“The forms of supplements we are using at the minute are measurably not safe, and I think that if industry ignores that fact, or refuses to engage, it may be opening itself up to liability in the future,” he warned.
Close scrutiny
Industry groups have been quick to react to the study; 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.”
“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
Reid responded by adding that he knew the research findings would be “a high stake statement.” He said 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.
Source: British Medical Journal
Published online ahead of print, doi:10.1136/bmj.d204
“Calcium supplements with or without vitamin D and risk of cardiovascular events: reanalysis of the Women’s Health Initiative limited access dataset and meta-analysis”
Authors: M.J. Bolland, A. Grey, A. Avenell, G.D. Gamble, I.R. Reid
7 comments (Comments are now closed)
What which Calcium? The good & Bad
Calcium?-<Cabonate Bad>. Citrate for women only.Calcium D-Glucarate with magnesium, iron, iodine, minerals glandulars and supporting cranberry Colagen and ginger.
Must also not use alcohol drugs and products containing synthetics and preservatives
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Posted by Harry
02 May 2011 | 10h50
Nutrition from food
Jerry: Taking pills "to fill the gaps" sounds good, but there are supplements available, in capsule form, which contain whole food concentrates containing much, hopefully most of the goodness of the original foodstuffs (fruits and vegetables). This, in my opinion, is the way to go. Sorry, Nutraingredients!
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Posted by Hugo Ross
27 April 2011 | 18h41
Revised, but still lacking
It was good they realized they missed the importance of vitamin D, but they missed the critical point that bone needs much more than calcium and D.It was also interesting that an editorial in the same journal said the results could not support not confirm.
Those women taking calcium supplements actually had a decrease risk of heart disease. THey also point out that the same authors had a previous study with the exact opposite conclusion.
Bone also needs magnesium, manganese, copper, and zinc. And bone formation needs K and D. If any are deficient, the calcium might just end up coating the arteries. One should take a look at Gladys Block's landmark study from Berkeley (Nutritional Journal 2007) where you will see taking multiple supplements for 20 years showed reduced heart attack and stroke risk. But of course this study was using a superior designed supplement list.
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Posted by Mike Grubic
26 April 2011 | 18h33
My Dear Nutritionist Friends
While I whole heartedly agree that getting your nutrition from food is the very best way to achieve good health, making that statement in today's or any day's world is unhelpful at best.
Telling that to a person who thinks good nutrition is eating the salad at McDonalds is a waste of breath. Ditto for those that thinks they should purchase a "food" because of the claims on the package or the contents or the nutrition facts panel on the back. These people appear to be in the majority in the US and perhaps other places in the world.
They clearly can not get their nutrition from a freezer meal or the drive through and no manner of discussion will change that fact. Perhaps, just perhaps if they grab a pill or two of the right kind, they just might stay off the disabled list for long enough so those who understand to correct the long list of problems in our food supply thus make it once again possible get our nutrition from food.
Till then I will continue to encourage my family and friends to take the pills to fill in the gaps where it makes sense according to the research we have.
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Posted by Jerry Segers
23 April 2011 | 05h23
Try K2
Did they check for blood levels of K2, which has been shown to reduce blood calcium and put it back in the bones.
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Posted by John Johnson
22 April 2011 | 05h27
Source of calcium
As a non-nutritionist I suggest that supplementation is NOT the way to go. By adding calcium, magnesium, boron, vitamin this and vitamin that and all of the other bits and pieces, what are you trying to achieve? Effectively you're trying to emulate nature but you can't do that. A nutritionist should be helping people to change their diet, not supplement individual micronutrients. We just don't understand how they react with each other, as this and countless other studies show. Whole food is the way to go, not ever more complex supplements.
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Posted by Hugo Ross
21 April 2011 | 08h26
calcium
As a nutritionist I would suspect that the real problem with this research is that calcium without magnesium is the problem. The more calcium one takes the more magnesium they need to balance it. Calcium, magnesium, vitamins D and K are all essential for the body to utilize the calcium. Many feel that boron is also essential. Without magnesium and with too much unbalanced calcium, there could be heart problems.
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Posted by Kathleen O'Bannon, CNC
20 April 2011 | 18h56
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