You are misquoting me…
You are right and I apologize for being lazy and not going back to your post. Instead of what I typed, "Simply saying “Everyone knows…” I should have copied and pasted from your post: It is very well known that vit D in quantities over 4000 IU can lead to broken bones. Post Number: 641389 Not sure that there is much difference between “everyone knows” and “it is very well known,” but indeed it was not a direct quote and again, lazy on my part.
Thank you for the link to the actual study. From what I am reading, they conclude that while radial bone density is statistically reduced more in the 4,000 IU and 10,000 IU level of supplementation when compared to the 400 IU level, only at 10,000 IU is there a statistical difference in the tibial bone density. Even with those differences in bone density, there was no significant differences in bone strength. It is concluded that higher levels of vitamin D supplementation are not beneficial to bone health, but it is also stated that more research needs to be done to see if the supplementation at higher levels is harmful. It does not support your theory IMO that “vit D in quantities over 4000 IU can lead to broken bones.” The study itself states this: There was no effect on fall rates in this study and no evidence of a relationship between changes in volumetric BMD and fracture risk…
Here is the direct copy and paste from the study: Conclusions and Relevance Among healthy adults, treatment with vitamin D for 3 years at a dose of 4000 IU per day or 10?000 IU per day, compared with 400 IU per day, resulted in statistically significant lower radial BMD; tibial BMD was significantly lower only with the 10?000 IU per day dose. There were no significant differences in bone strength at either the radius or tibia. These findings do not support a benefit of high-dose vitamin D supplementation for bone health; further research would be needed to determine whether it is harmful.
I also found this interesting: “Clinical trial data support skeletal benefits of vitamin D supplementation in persons with circulating 25-hydroxyvitamin D (25[OH]D) levels of less than 30 nmol/L.” But then it is stated that the very people with low vitamin D levels in their blood that should be helped by supplementation are eliminated from the study: “1 Participants were excluded if their screening serum 25(OH)D was less than 30 nmol/L or greater than 125 nmol/L;” So they tested the use of supplementation on those who did not need it? In the data it shows that the baseline D levels were 76.3, 81.3, and 78.4 respectively for the 400IU, 4,000IU and 10,000IU groups. Those levels are not indicative of needing D supplementation at all. So why should it surprise us that giving large doses of supplemental vitamin D to those who didn’t need it in the first place, would not be helpful?
nmol/L* ng/mL* Health status
<30 <12 Associated with vitamin D deficiency, which can lead to rickets in infants and children and osteomalacia in adults
30 to <50 12 to <20 Generally considered inadequate for bone and overall health in healthy individuals
=50 =20 Generally considered adequate for bone and overall health in healthy individuals
>125 >50 Linked to potential adverse effects, particularly at >150 nmol/L (>60 ng/mL)
I could go deeper into this, but given it is the wrong board I will simply note that any nutrition study that does not control the food intake, rather estimating what is being consumed by “assessed by a food frequency questionnaire,” is subject to large error. I am also surprised that there was no control group of 0 IU Vitamin D, while still receiving the Calcium supplements that were given when dietary calcium was deemed too low via the food frequency questionnaire. The lack of a vitamin K2 supplement in conjunction with the Ca supplement is probably some of the cause of the hypercalcemia they experienced during the study. Add to that the fact that they had quality problems with the high dose drops, (and why was the dose by drop rather than a capsule, when we are talking 2000IU PER DROP for the higher dose group, it’s not hard to overdose!!!)
To their credit, at the end of the study they too admit to the above under the section called Limitations. Here again is the link to the study: https://jamanetwork.com/journals/jama/fullarticle/2748796#:~…
I am not saying these studies are easy to read, but almost always if you wade through them you will reach a different conclusion than the pablum the general press puts out.
hoping after all this it is remembered that Vitamin D is also beneficial for your immune system and thought to help protect against cancer