National Institutes of Health funded a process that received 25,871 healthy American men and women aged 50 or older, of which 5,106 African Americans. Study participants were divided into four groups and randomized to use supplements or placebo and were followed for 5.3 years on average.
One group used daily 2,000 IU (international units) of vitamin D3 and 1 gram of omega-3 a day. The second group received vitamin D and the pill instead of omega-3. The third group received omega-3 and placebo with vitamin D. The last group received two placebo.
Pharmavite LLC, Northridge, California, donated vitamin D agents and the corresponding placebo and Pronova BioPharma from Norway, and BASF donated Omacor, a fish oil sold under the Lovaza brand in the United States.
Results published in the New England Journal of Medicine are presented on Saturday at the American Heart Association in Chicago.
In many ways, the results are not surprising. The public has been suppressed in recent years by a steady stream of information on vitamin D benefits in the field of health because studies link low vitamin levels to various diseases such as diabetes, high blood pressure, cancer, heart disease and depression. Many primary care physicians now routinely test vitamin D levels in patients and claim them to be inadequate, and additional sales have increased in recent years.
But all the time, critics have questioned whether vitamin D is only a health indicator and whether the deficiency threshold is too high. The so-called sun ray is synthesized in the body when the skin is exposed to sunlight and is exhausted by smoking, obesity, poor nutrition, and other factors. Some foods such as oily fish, eggs and milk also contain vitamin D.
The Institute of Medicine concluded in 2011 that most Americans received enough vitamin D and that the shortcomings were overestimated. The group also noted that reports of potential benefits with higher blood levels are inconsistent.