Could too much calcium be bad for your heart?

NEW YORK - In a new analysis from the National Institutes of Health, men who took calcium tablets were more likely to die of heart disease over more than a decade than those who didn't get extra calcium in supplement form.

"The effect of supplemental or dietary calcium on heart disease has always been a bit of an unanswered story," said Howard Sesso, a preventive medicine researcher at Brigham and Women's Hospital and Harvard Medical School in Boston.

"It could be that when you take supplements, maybe you're taking doses that far exceed what you need," he added. But it's still unclear how that might raise cardiovascular risks.

The new findings are based on a study of close to 400,000 middle-aged Americans initiated in 1995 to 1996.

Study volunteers answered questions about their lifestyle, general health and diet, including use of supplements. Researchers then tracked how many of them died, and from what causes, over the next 12 years.

About half of men and more than two-thirds of women said they took calcium supplements or multivitamins containing calcium at the outset.

During the study period, almost 12,000 people - or about 3% - died of cardiovascular disease.

Qian Xiao from the National Cancer Institute and her colleagues found men who took 1,000 milligrams of calcium per day or more were 20% more likely to die of heart-related causes than those who passed on calcium supplements. That was after the researchers took into account men's age, race and weight, as well as other measures of diet and lifestyle.

However, there was no link between calcium supplements and heart disease deaths in women. And calcium from food and beverages wasn't tied to heart problems in men or women, the research team wrote Monday in JAMA Internal Medicine.

It's possible that calcium build-up in the arteries and veins may affect cardiovascular risks in some people, Xiao wrote in an email to Reuters Health.

No cause-effect link

But Sesso, who wasn't involved in the new study, told Reuters Health he wasn't sure why, biologically, calcium supplements would be linked to a higher risk of heart problems in men but not women.

The findings don't prove a cause-and-effect link between the supplements and heart problems. It's possible there were certain differences between men who did or didn't take extra calcium that the research team couldn't measure.

"Although we observed an increased risk of death from heart disease in men who reported taking supplements containing calcium, we cannot say for sure that it was a result of using those supplements," Xiao said.

According to Sesso, the study won't change the fact that calcium supplements are typically recommended for reasons not related to heart disease - such as to prevent fracture risk in older adults who don't get enough calcium through food.

Eating a balanced diet and keeping a healthy weight are as or more important than any supplement when it comes to cardiovascular health, Sesso said.

"If you have a good diet in the first place, a supplement might not be adding all that much," he said.

source: abs-cbnnews.com

Vitamin D - plus calcium - tied to extra years

Older people who take vitamin D and calcium supplements may live a bit longer than their peers, according to an international review of several studies covering more than 70,000 people.

Researchers writing in the Journal of Clinical Endocrinology found that older people who were given the supplements were 9 percent less likely to die over three years than those given placebo pills. Vitamin D alone had no impact on death rates.

A 9 percent dip in death risk over a three year period might sound small, but lead researcher Lars Rejnmark said that effect is "at least as pronounced" as the benefits linked to cholesterol-lowering statins and blood pressure drugs.

"In my view, a 9 percent reduced mortality in the general population of elderly is of major importance," Rejnmark, an associate professor at Aarhus University in Denmark, told Reuters Health by email.

"Except for stopping smoking, there are not many other known interventions that are capable (of) such a reduction in the risk of death."

Rejnmark and his colleagues combined the results from eight clinical trials that involved more than 70,000 older adults, mostly women.

In each trial, people were randomly assigned to take vitamin D or a placebo. Some studies used a combination of vitamin D and calcium.

The doses varied, but most trials used a daily vitamin D dose of 10 to 20 micrograms. In the United States, health officials suggest that most adults get 15 micrograms (or 600 IU) of vitamin D per day, while people older than 70 should aim to get 20 micrograms (or 800 IU).

In trials that used calcium, the dose was 1,000 milligrams per day. In general, women older than 50, and everyone over 70, are told to get 1,200 milligrams of calcium each day.

Vitamin D and calcium are probably best know as bone-builders. Older women often take the supplements to ward off the bone-thinning disease osteoporosis - and some trials have found that the supplement combination can prevent falls and bone fractures in the elderly.

But that probably does not explain the lower death risk in this study. When the researchers factored in hip and spine fractures, they did not account for the dip in death risk.

Another possibility is that supplements curbed people's risk of dying from cancer. Rejnmark said there's some evidence that calcium and vitamin D may lower the odds of colon cancer, but the evidence is not yet "firm".

For now, he said, the findings supported getting the recommended amounts of vitamin D and calcium.

Some members of Rejnmark's team had connections to supplement makers that market vitamin D and calcium products.

source: interaksyon.com