Vitamin D, if taken regularly and in doses higher than 400 IU daily, reduces fractures by up to 20% in older adults. So say researchers in a meta-analysis published in this month’s Archives on Internal Medicine.
Previous studies on the efficacy of vitamin D in preventing fractures have shown conflicting results, with some finding a benefits and others not. A team of Swiss and American researchers hypothesized that this variability in effect might be because some studies used too low a dose of Vitamin D and others did not accurately measure whether subjects even took the Vitamin D they were given. (We call that adnerence to therapy.) In addition, many previous studies did not control for baseline vitamin D levels or measure whether levels were actually increased with therapy.
In a complicated but nicely done meta-analysis, these researchers culled the cream of the crop of randomized clinical trails of vitamin D supplementation and fracture risk. Only studies that used higher doses of vitamin D, measured blood levels of Vitamin D and assessed subjects’ adherence to therapy were included in the analysis. The researchers compared fracture risk according to vitamin D dose and levels.
What they discovered was that doses of vitamin D of 400 IU daily were not effective in preventing fracture. Higher doses were – to the tune of a 20% reduction in non-vertebral fractures and an 18% reduction in vertebral fractures in individuals over age 65. (This is actually something that has been suspected for some time now, and in fact the current recommended daily dose of Vitamin D is 800 IU daily, with some saying that we should increase that further to 1200 IU daily.)
In support of the effect, fracture reduction was related to vitamin D levels, with higher levels showing greater reduction, up to a level of 112 nmol/ml (about 40 ng/ml). The benefits of vitamin D were seen irrespective of calcium supplementation.
The researchers recommend that future studies of Vitamin D and fracture risk use higher doses and longer duration of therapy, and measure both adherence to therapy and serum levels of vitamin D.
Take Home Message
Vitamin D indeed appears to be effective in reducing fracture risks, provided you adhere to your treatment and take over 400 IU daily. I’d recommend 800 IU daily. (And 1200 IU won’t hurt you…)
I’ve been measuring vitamin D levels in my patients with low bone mass, and have been not surprised to find that most of them are deficient. I love that I have an intervention for them that is both safe and inexpensive.
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Prevention of Nonvertebral Fractures With Oral Vitamin D and Dose Dependency. A Meta-analysis of Randomized Controlled Trials. Heike A. Bischoff-Ferrari, DrPH; Walter C. Willett, DrPH; John B. Wong, MD; Andreas E. Stuck, MD; Hannes B. Staehelin, MD; E. John Orav, PhD; Anna Thoma, MD; Douglas P. Kiel, MD; Jana Henschkowski, MD. Arch Intern Med. 2009;169(6):551-561.
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11/30/10 UPDATE
New IOM guidelines recommend vitamin D intake of 600 IU daily for adults up to age 70, and 800 IU daily for those age 71 and older.
What about using your email inbox for the ticklers and setting up a separate folder that has the radiology scan results, and another for those “problem” patients that you are trying to track? Would that be better than a paper system that you didn’t have to cart around?
is there any down side to 800 or 1200 IU daily?
what are some ideas about getting compliance with those doses? i ask because i’m notoriously bad with pills — it takes an effort to remember the full 10 days of an antibiotic, for example, and forget daily vitamins. probably i need to train myself, somehow.
To help me remember to take my vitamins I have resorted to the same method used by my 80-year-old parents…the old pill box. Nowadays you can get the 7 day pill sorter that holds up to 10 pills or more. I fill it up with a week’s worth of vitamins on Sunday nights and then keep it in my bag that I carry to work every day. When I get to work I get my things from my work bag and can;t miss the pill sorter so no chance of forgetting to take the pills. I fill my 48 ounce water jug (a way of getting my 8 glasses in per day) and start swallowing. I recently added calcium to my daily regimen as I hardly ever get any milk in my diet and now I will be adding Vitamin D.
– OBS Housekeeper
Supplements are my answer for my lack of Vitamin D. I personally find it really hard to get my daily dose of D from the Sun or diet. I work full time and spend a lot of time in-doors. Our family now takes a supplement we found from Wellesse. They make a liquid Vitamin D Supplement that is a great tasting liquid. It makes it easy for me to dose my whole family. No pills to swallow for the kids and easily absorbed. Check it out at http://www.wellesse.com for more info.
thanks for the suggestions!
Kathy and anonymous –
if remembering a daily dose os difficult, one can take a weekly dose of 10,000 IU. One site that sells it is vitd3.com.
David –
Thanks for the suggestion – it wont; work for me, unfortunately, because I am one of those folks who needs to have a near empty in box in order to feel sane.
well, i’m going to go with the pill box, and try to find a calcium/d supp in pill form or similar. something that will fit in the box, because i need a new routine to be simple, especially since i need some other new routines.
because crappity crap, my neglect of self has gone and caught up with me, and it turns out i have high blood pressure. so, needing a daily pill for that is a perfect excuse to finally get real about the calcium/D supplements [maternal history of osteoporsis] and multivitamins. and whatever the future holds in terms of daily doses.
yes, dr. tbatm, i’m also working on how to up the exercise without feeling like i’m doing a forced march — and what looks to be a big job, examining everything for sodium content to eliminate as much as possible. bleah.