“Is vitamin D beneficial?” is (or has become) one of the frequently asked questions by both our patients and their peers. Indeed, there has been a marked increase in researchers’ interest in vitamin D in recent years, and there is considerable research suggesting that nearly all known diseases are somehow related to vitamin D.
As you can imagine, the common result of these studies is “Vitamin D is beneficial”. However, when the conclusions of most of these studies are examined, it is not overlooked that the researchers were somewhat hesitant to make a direct recommendation such as “increase your vitamin D intake”. Now, in response to the question at the beginning of the article, although one’s instinct is to give a reflexive and evasive answer saying, “It is useful, of course, since it contains vitamin in its name,” the truth of the matter seems a little more complicated than it seems. Even if there is general evidence that it is beneficial, “for whom is it useful?”, “In what situations is it useful?”, “It is useful at what dose?” Questions like these need to be answered first.
One of the most researched subjects, which is thought to have positive effects of vitamin D, is the effects of vitamin D on falls and fracture development. Most previous clinical studies (although there are some inconsistencies) suggest that vitamin D reduces the development of falls and fractures. According to the results of previous studies, it has been shown that daily intake of 700-800 units of vitamin D reduces the risk of fracture by 13-26% and the risk of falling by 19-26%. In addition, these studies revealed that one of the most important problems with vitamin D is patient compliance, that is, patients are not very willing to use the drug regularly every day. Therefore, Sanders et al. planned the study, published in JAMA on May 12, 2010, to facilitate the use of vitamin D, the benefit of which has already been shown, to use it once a year (high dose) rather than every day (low dose), the incidence of falls and the development of fractures. They asked the question, what are the effects on it?
The study was conducted in a single center in Australia between 2003 and 2008. Of 2258 women who are over 70 years old and have at least 1 risk factor for hip fracture (mother’s hip fracture, previous fracture history, etc.), 500 000 Units of cholecalciferol (vitamin D3) was given orally once a year to one part of them and placebo to the other part. Participants were followed for 3-5 years. The participants were asked to write the falls on their calendar, and the fractures were already recorded with the x-ray taken.
Let’s come to the results of the study; When people given vitamin D were compared with those given placebo, there was a 15% increase in the frequency of falls and a 26% increase in the frequency of fractures. If you’re thinking of re-reading the sentence you just read, thinking that you misread it or that there is a typo, there is no need for it. The researchers also performed many additional analyzes that we cannot include here, but this did not change the conclusion that high doses of vitamin D INCREASE the risk of falls and fractures. Another remarkable feature among the results of the study is that the frequency of both falls and fractures increases significantly within the first 3 months following the administration of the drug (which somehow supports that vitamin D is responsible for falls and fractures). Frankly, researchers had a hard time trying to interpret this (unexpected) result. Currently, the recommended dose of vitamin D for individuals over 70 years of age in the USA and Canada is 600 Units per day (upper limit of 2000 Units, which is equivalent to 700 000 Units per year). Based on this, the researchers commented that the problem here might be the administration of such a high dose in one go, rather than the high dose.
Actually, the most important thing that this study tells us (or reminds us) is that we should not think straight about anything related to the human body. It would certainly be more interesting if the researchers’ hypothesis were true and the title of this article was “vitamin D taken once a year is a panacea”, but the account at home does not always fit the market.
