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Big studies give mixed news on fish oil, vitamin D

CHICAGO – Taking fish oil or vitamin D? Big studies give long-awaited answers on who does and does not benefit…

CHICAGO – Taking fish oil or vitamin D? Big studies give long-awaited answers on who does and does not benefit from these popular nutrients.

Fish oil taken by healthy people, a dose found in many supplements, showed no clear ability to lower heart or cancer risks. Same for Vitamin D.

But higher amounts of a purified, prescription fish oil slashed heart problems and heart-related deaths among people with high triglycerides, a type of fat in the blood and other risks for heart disease. Doctors cheered the results and said they could suggest a new treatment option for hundreds of thousands of patients like these.

Up to 10 percent of US adults take fish oil. Even more take vitamin D, despite no major studies to support the many health claims made for it.

“Those who peddle it promote it as good for everything,” but in this definitive test, vitamin D “showed a big nothing, “Said Dr. James Stein, a heart specialist at the University of Wisconsin-Madison.

Results were revealed at an American Heart Association conference in Chicago and published by the New England Journal of Medicine.

About fish oil ]

These oils, also called omega-3 fatty acids, are found in salmon, tuna and certain other fish. They reduce triglycerides and inflammation and may have other effects. There are different types, including EPA and DHA.

One study tested 4 grams a day of Amarin Corp.’s prescription Vascepa, which is concentrated EPA, in more than 8,000 patients with high triglycerides and a greater risk of heart problems for various reasons. All were already taking a statin such as Lipitor or Zocor to lower cholesterol. Half was given Vascepa and the rest, mineral oil capsules as a comparison.

After five years, about 1

7 percent of those on Vascepa had suffered from one of these problems: a heart attack, stroke, heart-related death or clogged arteries requiring medical care – versus 22 percent of the others.

That worked out to a 25 percent reduction in risk. Looked at individually, heart attacks, heart-related deaths and strokes were all lower with Vascepa. Only 21 people would need to take Vascepa for five years to prevent one of the main problems studied – favorable odds, Stein said.

Side effects may be a concern: More people on Vascepa were hospitalized for an irregular heartbeat – 3 percent versus 2 percent of the comparison group. Doctors say that’s puzzling because other research suggests fish oil lowers that risk.

The concern with the heart rhythm problem is that it can raise the risk of stroke, but there were fewer strokes among those on Vascepa, said study leader. Deepak Bhatt of Brigham and Women’s Hospital in Boston.

Vascepa costs around $ 280 a month; many insurers cover it. Amarin sponsored the study and some study leaders work or consult for the company.

A broader test

The other study tested a lower 1 gram daily dose of a different type of fish oil – an EPA / DHA combo sold as Lovaza or Omacor and in generic form – In 26,000 people with no prior heart problems or cancer.

After about five years, rates of a combined measure of heart attacks, strokes and other problems were similar to fish oil users and a comparison group. Cancer rates and deaths were also similar.

There were fewer heart attacks in the fish oil group – 145 versus 200 in the comparison group. The study leader, Dr. JoAnn Manson at Brigham and Women’s, called that “a substantial benefit,” but several independent experts disagreed because of the way the study was set up to track this and certain other results.

“Disse resultater er spekulative og skulle være confirmed in a separate trial, “said the Cleveland Clinic’s Dr. Steven Nissen.

Fishy comparisons?

Both studies share a problem: the oils used for the comparison groups, which may not have been true placebos. The Vascepa study used mineral oil, which interferes with statin drugs, raises cholesterol and might have made the comparison group worse and made Vascepa look better than it truly was.

The other study used olive oil, which might have helped that comparison

Leaders of both studies say any effect from the comparison oils is not enough to change the main results and independent experts agreed. But Nissen, who is leading another fish oil study, uses corn oil as a comparison.

The ‘sunshine’ vitamin

Manson’s study also tested vitamin D, which the skin makes from sun exposure . It’s tough to get enough from foods like milk, eggs and oily fish, though many foods now are fortified with it.

Study participants took 2,000 international units of D-3 (the most active form of vitamin D, which is the most active form of vitamin D, also called cholecalciferol) or fake vitamin pills for five years.

Vitamin D did not affect the odds of having a heart attack or stroke or developing cancer. Efter at have eksportert de første to årene, brugte forskere færre kræftdød blandt dem på vitamin – 112 versus 149 i placebo-gruppen.

“Cancer kan tage år å udvikle”, så en forskjell kan ikke komme opp straks, Manson said. “This looks promising” and people will be studied longer to see if the trend keeps up, she said.

“These ‘several’ experts said these numbers just hint at a possible benefit that needs more study. positive results need to be interpreted with caution, “Dr. Clifford Rosen of Maine Medical Center Research Institute and Dr. John Keaney Jr. of the University of Massachusetts wrote in a commentary in the medical journal.

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