Vitamin D supplements don’t help other health conditions, study finds

The idea was so sensible that it was accepted almost without question: vitamin D pills can protect bones from fractures. After all, the body needs a gut vitamin to absorb the calcium that bones need to grow and stay healthy.

But now, in the first large federally funded randomized controlled trial in the United States, researchers report that vitamin D tablets, taken with or without calcium, do not affect the incidence of bone fractures. results, achievements, published Thursday in The New England Journal of Medicinerecommended for people with osteoporosis and even for those whose blood tests have revealed vitamin D deficiency.

These results follow other findings from the same study, which found no support for a long list of supposed benefits of vitamin D supplements.

So, for the millions of Americans who take vitamin D supplements, and for the labs that perform more than 10 million vitamin D tests every year, editorial published along with the paper has some advice: Stop.

“Physicians should stop screening for 25-hydroxyvitamin D levels or recommend vitamin D supplements, and people should stop taking vitamin D supplements to prevent serious illness or prolong life,” the doctor wrote. Stephen R. Cummings, Research Fellow, California Pacific Medical Center, and Dr. Clifford Rosen, Senior Fellow, Maine Medical Research Institute. Dr. Rosen is editor of the New England Journal of Medicine.

There are exceptions, they say: People with conditions like celiac disease or Crohn’s disease need vitamin D supplements, as do those who live in environments where they are deprived of sunlight and may not be getting any minerals from foods. to which vitamin D is commonly added, such as cereals and dairy products.

Getting into such a severe state of vitamin D deficiency is “very difficult in the general population,” says the doctor. Cummings said.

The two scientists know that by making such strong claims, they are challenging vitamin vendors, testing labs and advocates who claim that taking vitamin D, often in massive amounts, can cure or prevent a wide range of diseases and even help people live longer.

Doctors often check vitamin D levels as part of routine blood tests.

The study included 25,871 participants—men aged 50 and over and women aged 55 and over—who were assigned to take 2,000 international units of vitamin D daily or a placebo.

The study was part of a comprehensive vitamin D study called VITAL. It was funded by the National Institutes of Health and began after a panel of experts convened by the non-profit organization now called the National Academy of Medicine studied the health effects of vitamin D supplements and found little evidence. Members of the expert panel were supposed to determine the minimum daily requirement for the vitamin, but found that most of the clinical trials that looked into this were inadequate, leading them to question whether there was any truth to the claims that vitamin D improves health.

At the time, the prevailing view was that vitamin D likely prevented bone fractures. The researchers thought that if vitamin D levels dropped, parathyroid hormone levels would increase, which would wreak havoc on the bones.

Dr. Rosen said those concerns prompted him and other members of the National Academy of Medicine’s expert panel to establish what he called an “arbitrary value.” 20 nanograms per milliliter of blood as a target vitamin D level. and advise people to get 600 to 800 international units of vitamin D supplements to achieve this goal.

Laboratories in the United States then arbitrarily set 30 nanograms per milliliter as the cut-off point for normal vitamin D levels, a reading so high that nearly everyone in the population would be considered vitamin D deficient.

The proposed relationship between vitamin D levels and the parathyroid gland has not been confirmed in subsequent studies. Rosen said. But uncertainty persisted, so the National Institutes of Health funded the VITAL study to get solid answers about vitamin D’s relationship to health.

The first part of VITAL, published earlier, showed that vitamin D did not prevent cancer or cardiovascular disease in test participants. And it’s not prevent fallingimprove cognitive functioningreduce atrial fibrillationchange body compositionn, reduce migraine frequencyimprove strike outcomesprotect from macular degeneration or reduce knee pain.

Another major study in Australia found that people who took the vitamin did not live longer.

Dr. Joanne Manson, head of preventive medicine at Harvard Medical School’s Brigham and Women’s Hospital and head of the pivotal VITAL study, said the study was so large that it included thousands of people with osteoporosis or with vitamin D levels in the range considered low or “low”. insufficient.” This allowed the researchers to determine that they also received no fracture reduction benefit from the supplement.

“Many people will be surprised by this,” the doctor says. Manson said. “But we only seem to need a small to moderate amount of the vitamin for bone health. Big sums don’t give big benefits.”

First author of the bone study and principal investigator, Dr. Meryl S. LeBoff, an osteoporosis expert at Brigham and Women’s Hospital, said she was surprised. She expected benefits.

But she cautioned that the study did not address the question of whether people with osteoporosis or low bone mass should take vitamin D and calcium along with osteoporosis medications. Professional advice says they should take vitamin D and calcium, and she will continue to follow them in her practice.

Dr. Dolores Shobak, an osteoporosis expert at the University of California, San Francisco, will also continue to advise patients with osteoporosis and low bone mass to take vitamin D and calcium.

“This is a simple intervention and I will continue to prescribe it,” she said.

Others go a little further.

Dr. Sundeep Khosla, a professor of medicine and physiology at the Mayo Clinic, said that because vitamin D “would do little or no harm, but could do some good,” he would continue to advise his osteoporosis patients to take it, recommending 600 to 800 mg. units per day in the report of the National Academy of Medicine.

“I will still tell my family and friends who don’t have osteoporosis to take a multivitamin a day to make sure they don’t have a vitamin D deficiency,” he said.

Dr. Khosla himself follows this advice. He added that many multivitamin tablets now contain 1,000 units of vitamin D.

But dr. Cummings and Dr. Rosen remains firm, even questioning the very idea of ​​vitamin D deficiency in healthy people.

“If Vitamin D Doesn’t Help, What Is a Vitamin D Deficiency?” Dr. Cummings asked. “That means you have to take vitamin D.”

And etc. Rosen, who signed the National Academy of Medicine report, became a therapeutic vitamin D nihilist.

“I don’t believe in 600 units anymore,” he said. “I don’t think you should do anything.