USPSTF concludes that the current evidence is insufficient to assess the balance of the benefits and harms of daily supplementation with >400IU of vitamin D3 and 1,000mg of calcium for the primary prevention of fractures in noninstitutionalized postmenopausal women. Here we need to go back and read the meta-analysis very carefully: "combined vitamin D and calcium supplementation reduced fracture risk in older adults, but the effects differed according to study setting: institution vs community dwelling." If you lump all older adults together, you get a 12% relative risk reduction but that's mainly due to a 29% relative risk reduction in those who are institutionalized vs a not-statistically significant relative risk reduction in community-dwelling elderly. Lumpers vs splitters. Looks like I need to join the crowd moving towards individualized & personalized medicine.
USPSTF recommends against daily supplementation with <400IU of vitamin D3 and 1,000mg of calcium carbonate for the primary prevention of fractures in noninstitutionalized postmenopausal women. This is the recommendation that has really been blown out of the water and taken out of context. Yes, it's a grade D recommendation but the USPSTF isn't saying no to vitamin D (as implied in the lay press), they're just saying no to piddly doses of vitamin D (don't forget the lumpers vs splitters argument above).
The point is that 200IU of vitamin D3 isn't really going to do anything for you but soothe your conscience, so why waste your money? If you're going to take vitamin D, I recommend that you taken enough to bring your 25OH vitamin D3 levels above at least 30ng/mL (personally, I'd aim for >50ng/mL but that's just me). Which means that you have to check your levels, just like you do your cholesterol if you take a statin and your blood pressure if you take an antihypertensive. And let's not forget the recent study, continuing a trend of studies, albeit mostly from one author, suggesting that calcium supplementation (as opposed to dietary calcium) is associated w/heart disease.
Finally, USPSTF has previously concluded in a separate recommendation that vitamin D supplementation is effective in preventing falls in community-dwelling adults aged 65 years and older who are at increased risk for falls. They felt so strongly about the evidence that they gave this statement a grade B recommendation.
Bottom line, there's a quite a bit of unavoidable overlap. After all, if you decide to take vitamin D to prevent falls, it's not like you can tell your vitamin D not to prevent cancer or fractures! The point is that you need to know why you're doing something and to do it for the right reason(s). And if there's some potential side benefit, then so be it. As always, make sure the risk vs benefit calculus works out in your favor. Vitamins & minerals, just like medications, herbs, and dietary supplements are double-edged swords, able to do both good & harm. So choose wisely!
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