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Low vitamin D linked to heart disease

In people with low blood levels of vitamin D, boosting them with supplements more than halved a person’s risk of dying from any cause compared to someone who remained deficient, in a large new study.

Analyzing data on more than 10,000 patients, University of Kansas researchers found that 70 percent were deficient in vitamin D and they were at significantly higher risk for a variety of heart diseases.

D-deficiency also nearly doubled a person’s likelihood of dying, whereas correcting the deficiency with supplements lowered their risk of death by 60 percent.

“We expected to see that there was a relationship between heart disease and vitamin D deficiency; we were surprised at how strong it was,” Dr. James L. Vacek, a professor of cardiology at the University of Kansas Hospital and Medical Center, told Reuters Health.

“It was so much more profound than we expected.”

Vitamin D deficiency has been linked to a range of illnesses, but few studies have demonstrated the reverse — that supplements could prevent those outcomes.

Vacek and his team reviewed data from 10,899 adults whose vitamin D serum levels had been tested at the University of Kansas Hospital, and found that more than 70 percent of the patients were below 30 nanograms per milliliter, the level many experts consider sufficient for good health.

After taking into account the patients’ medical history, medications and other factors, the cardiologists found that people with deficient levels of vitamin D were more than twice as likely to have diabetes, 40 percent more likely to have high blood pressure and about 30 percent more likely to suffer from cardiomyopathy — a diseased heart muscle — as people without D deficiency.

Overall, those who were deficient in D had a three-fold higher likelihood of dying from any cause than those who weren’t deficient, the researchers reported in the American Journal of Cardiology. Moreover, when the team looked at people who took vitamin D supplements, their risk of death from any cause was about 60 percent lower than the rest of the patients, although the effect was strongest among those who were vitamin D deficient at the time they were tested.

The study does not prove that vitamin D is the cause of the effects seen — other factors, like disease, could be responsible both for the differences in health and the differences in vitamin D levels, for instance.

Previous research has indicated that many Americans don’t have sufficient levels of vitamin D, however. The latest National Health and Nutrition Examination Survey estimated that 25 percent to 57 percent of adults have insufficient levels of D, and other studies have suggested the number is as high as 70 percent.

Vacek said he believes so many people are deficient because we should get about 90 percent of our Vitamin D from the sun and only about 10 percent from our food. The human body makes vitamin D in response to skin exposure to sunlight.

Certain foods, like oily fish, eggs and enriched milk products are also good sources of D. A sufficient amount of Vitamin D absorption from the sun would require at least 20 minutes of full-body exposure each day in warmer seasons, and most people aren’t outside enough, Vacek said.

In the northern United States and throughout Canada, experts say the sun isn’t strong enough during the winter months to make sufficient vitamin D, even if the weather was warm enough to expose the skin for a long time.

It means that adults should consider getting their Vitamin D levels checked through a simple blood test, Vacek said, and take vitamin D supplements. Generally, Vacek recommends that adults take between 1,000 to 2,000 international units (IU) of Vitamin D each day.

“If you’re not deficient, Vitamin D is not a magic pill that will make you live longer,” Vacek said.

“Its benefit is in people who are deficient. If you’re low, it makes sense to be put on replacement therapy and have a follow-up a couple months later to make sure your levels come up.” SOURCE: www.reuters.com/news/health

Mediterranean-ish diet tied to better heart health

CHINA-ECONOMY/CPI

Once again, eating a diet based on fish, legumes, vegetables and moderate amounts of alcohol is linked to lower chances of dying from a heart attack, stroke or other vascular “events,” according to a new study of New York City residents.

The mostly Hispanic and black study participants did not necessarily eat traditional foods from Mediterranean countries, but the closer their diets were to the spirit of Mediterranean eating — with plenty of fish, healthy fats like olive oil, whole grains and vegetables — the lower their risk of death from vascular problems including heart attacks.

“While it’s not the Mediterranean diet, it is comparing a healthier diet to a less healthy diet, and there was some improvement,” said Teresa Fung, a professor at Simmons College in Boston who was not involved in the study.

For nine years, Dr. Clinton Wright at the University of Miami and his colleagues followed more than 2,500 residents of northern Manhattan, a neighborhood with about 63 percent Hispanic residents, 20 percent African Americans and 15 percent whites. Information about the health benefits of a so-called Mediterranean diet in the black and Hispanic populations in the U.S. is lacking, Wright’s group notes in the American Journal of Clinical Nutrition.

Because both groups are burdened by high rates of heart disease, the team set out to study how much of a difference diet might make.

A little more than half of the study participants were Hispanic, while the other half was split roughly between non-Hispanic blacks and whites. All were over 40 years old when the study began.

At the outset, researchers asked participants about their health history, and ranked their eating habits along a nine-point scale: the higher the number, the closer the person’s diet was to the Mediterranean ideal, with lots of fish, vegetables, legumes, whole grains and vegetable oils and very little meat or animal fats.

The group then tracked how many people later experienced a stroke, heart attack or death related to a vascular problem like pulmonary embolism and aneurysm. More than 300 people in the study died from a vascular issue.

Each point higher that a person scored on the nine-point Mediterranean diet scale reduced the risk of vascular death by nine percent.

The study did not find that the diet had any effect on the risk of having a stroke, however. Among the 171 people who suffered a stroke, those at the high end of the diet scale were just as likely to have had one as those at the low end of the scale.

The researchers did detect slight protection from heart attack among those whose diets ranked in the top-four on the Mediterranean scale, but the finding could have been due to chance.

The results back up previous research that also reported benefits to heart health from eating a Mediterranean diet (see Reuters Health stories from March 7, 2011 and January 27, 2010).

The current study does not prove that diet is responsible for the benefits the researchers saw. But the Mediterranean diet is rich in elements like fiber and omega-three fatty acids, which could influence heart health, Wright said.

The evidence isn’t conclusive, he added, but overall, the Mediterranean diet appears to be good for people’s heart health.

“There’s very little evidence to suggest that it’s harmful compared to some other diets that we consider harmful, such as diets rich in red meat,” Wright said.

“So it seems like there isn’t much harm in it and there’s increasing evidence that it’s beneficial.”SOURCE: www.reuters.com/article/

Scientists find weakness in deadly Ebola virus

weakness

A protein that helps transport cholesterol inside cells may be a key to developing drugs to treat Ebola, a rare but lethal virus for which there are no known treatments, U.S. researchers said.

Laboratory mice bred to produce low levels of this protein — known Niemann-Pick C1 — survived exposure to both Ebola, which causes a hemorrhagic fever, and its cousin, Marburg virus.

“This research identifies a critical cellular protein that the Ebola virus needs to cause infection and disease,” said Sean Whelan of Harvard Medical School, who worked on one of two studies published on Wednesday in the journal Nature.

“The discovery also improves chances that drugs can be developed that directly combat Ebola infections,” Whelan said in a statement.

Ebola is one of the most deadly infections known, killing 90 percent of people infected by it.

It first emerged in 1976 in villages along the Ebola River in the Sudan and the Democratic Republic of the Congo, and is usually fatal in humans and in other primates such as monkeys, gorillas and chimpanzees.

So far, there have been about two dozen Ebola outbreaks in Africa.

No one knows how the virus is spread, and there are no available vaccines or anti-viral drugs that fight the infections.

But the new research suggests the virus has a weakness in the form of a well-known protein called Niemann-Pick.

People who have two abnormal copies of this protein develop Niemann-Pick disease, in which cells of the spleen, liver and brain become clogged up with cholesterol.

KEY PATHWAY

But this same protein also appears to be the key pathway Ebola uses to get deep inside cells.

“What we showed is this virus needs this protein,” Kartik Chandran, of Albert Einstein College of Medicine in New York, said in a telephone interview.

“Mice that have less of this protein are very resistant to being killed by Ebola and the Marburg virus,” said Chandran, who worked with researchers at Harvard, the U.S. Army Medical Research Institute of Infectious Diseases and the Whitehead Institute for Biomedical Research.

Chandran’s work focused on the mechanism used by Ebola to gain access to cells.

But a compound he helped discover in 2005 as a young researcher working in the lab of James Cunningham at Harvard has shown promise in blocking the Niemann-Pick protein in human cells, according to a separate paper led by Cunningham and co-authored by Chandran.

“Essentially, they were able to show this compound can block infection by the virus,” Chandran said of Cunningham’s team.

The compound has not yet been tested in mice, and would still need to show it is effective in non-human primates.

Chandran said blocking this critical compound long term would likely cause illness.

People with Niemann-Pick disease have two abnormal copies of the gene that make this protein, but the mice used in Chandran’s lab only had one working copy of this gene, suggesting that simply reducing the amount of the Niemann-Pick protein may help protect people from the virus.

Besides, Chandran said, most outbreaks are short-lived, so treatment would be needed for only a short time.

The researchers are optimistic that this new understanding of how Ebola gets into cells may eventually lead to treatments. But he acknowledges it will take many years, and possibly even a decade, before treatments would be available for human use.source: www.reuters.com/article/