High doses of Vitamin D can be bad for you

I often wonder whether the Left or the Right are more likely to be health freaks. In particular, who is more likely to be a pill popper?  I was amused to see how science fiction author and conservative blogger Bill Quick was attached to his "supplements".  He clearly believed that his daily dose of vitamins etc kept him healthy.  When I made skeptical comments about that (Me, skeptical?) he got on his high horse and unfriended me on Facebook and put a block on my email access to him. I was mightily amused by that act of religious devotion.  He even called me unscientific.  When a novelist calls an actual much-published scientist unscientific, that is amusing too.  It would have been interesting if he had tried to prove it but he did not

Anyway, there is plenty of literature showing that too much of anything tends to be bad for you.  I think the craze for high doses of vitamin C has now run its course by now, for instance.

The recent study below is only a small one but getting any significant effect from such a small sample over a short period is interesting. The point of the study was to find out if you could make oldsters (like Bill Quick) less shaky on their pins by dosing them up with a pile of vitamin D. Sadly, the hi-dose  vitamin just made them fall over MORE.

Some kind person should pass on a link to this to poor old Bill Quick. His site is Daily Pundit.  If it is of any interest, at age 72 I take no pills of any kind.  I have a weakness for gin, though

Monthly High-Dose Vitamin D Treatment for the Prevention of Functional Decline: A Randomized Clinical Trial

By Heike A. Bischoff-Ferrari, et al.


Importance:  Vitamin D deficiency has been associated with poor physical performance.

Objective:  To determine the effectiveness of high-dose vitamin D in lowering the risk of functional decline.

Design, Setting, and Participants:  One-year, double-blind, randomized clinical trial conducted in Zurich, Switzerland. The screening phase was December 1, 2009, to May 31, 2010, and the last study visit was in May 2011. The dates of our analysis were June 15, 2012, to October 10, 2015. Participants were 200 community-dwelling men and women 70 years and older with a prior fall.

Interventions:  Three study groups with monthly treatments, including a low-dose control group receiving 24 000 IU of vitamin D3 (24 000 IU group), a group receiving 60 000 IU of vitamin D3 (60 000 IU group), and a group receiving 24 000 IU of vitamin D3 plus 300 μg of calcifediol (24 000 IU plus calcifediol group).

Main Outcomes and Measures:  The primary end point was improving lower extremity function (on the Short Physical Performance Battery) and achieving 25-hydroxyvitamin D levels of at least 30 ng/mL at 6 and 12 months. A secondary end point was monthly reported falls. Analyses were adjusted for age, sex, and body mass index.

Results: The study cohort comprised 200 participants (men and women ≥70 years with a prior fall). Their mean age was 78 years, 67.0% (134 of 200) were female, and 58.0% (116 of 200) were vitamin D deficient (<20 ng/mL) at baseline. Intent-to-treat analyses showed that, while 60 000 IU and 24 000 IU plus calcifediol were more likely than 24 000 IU to result in 25-hydroxyvitamin D levels of at least 30 ng/mL (P = .001), they were not more effective in improving lower extremity function, which did not differ among the treatment groups (P = .26). However, over the 12-month follow-up, the incidence of falls differed significantly among the treatment groups, with higher incidences in the 60 000 IU group (66.9%; 95% CI, 54.4% to 77.5%) and the 24 000 IU plus calcifediol group (66.1%; 95% CI, 53.5%-76.8%) group compared with the 24 000 IU group (47.9%; 95% CI, 35.8%-60.3%) (P = .048). Consistent with the incidence of falls, the mean number of falls differed marginally by treatment group. The 60 000 IU group (mean, 1.47) and the 24 000 IU plus calcifediol group (mean, 1.24) had higher mean numbers of falls compared with the 24 000 IU group (mean, 0.94) (P = .09).

Conclusions and Relevance: Although higher monthly doses of vitamin D were effective in reaching a threshold of at least 30 ng/mL of 25-hydroxyvitamin D, they had no benefit on lower extremity function and were associated with increased risk of falls compared with 24 000 IU.

JAMA Intern Med. Published online January 04, 2016. doi:10.1001/jamainternmed.2015.7148

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