Maybe you should look at what the study actually did and said

No, the Washington post is not one of Marshall's rags although I would not put it on a par with Medical News Today or JAMA when it comes to reporting on health and medical science.  Like many mainstream publications, the Washington Post gets lots of mileage out of slanted headlines that often are not supported by what they are actually reporting on.

When you go to sources such as Medical News Today and JAMA, and look at the study, you will find that what the study actually was about and what the authors said and concluded are entirely different than some of the MSM headlines about "Vitamin D dangers".

The study was conducted a group of women age 70 and over who were given a single annual dose of vitamin D of 500,000 international units.  All you can infer from the study is that it is not a good idea to give women over 70 a single dose of vitamin D that is 25 times larger than the body will naturally make at one time and almost 1000 times greater than the average vitamin D supplement.

As the lead study author stated:

"The evidence suggests that a single large dose is too much vitamin D given at one time,"

Looking more closely at the study, you find an interesting pattern that emerged throughout the five year study:

"A posthoc analysis showed a temporal pattern for falls, with an incidence rate ratio of 1.31, favoring the placebo group, in the first three months after dosing and an incidence rate ratio of 1.13 during the following nine months."

Since serum levels remained high throughout the year for the women given the oral Vitamin D3 (they were still 41% higher right before the next annual dose), why do you suppose that the additional incidence of falls occured almost entirely within just the first three months after each dose?

According to two of the study authors, that pattern might be explained by a "protective" reaction, in which the enzyme that breaks down vitamin D was upregulated, according to Bess Dawson-Hughes, MD, and Susan Harris, DSc, both of Tufts University in Boston.

However, the authors had another explanation which they felt strongly enough about to include in an accompanying editorial they wrote for the study.  Said the authors:

It's also possible that women getting the supplement felt better in the first three months after treatment and therefore were more active. The additional activity might have exposed them to more opportunities to fall, they argued.

In other words, huge dose or not, the Vitamin D dose may well have had health benefits and it might not have caused problems with the women's bone health and falls or fractures at all.

Looking further you will also find that the authors did not conclude that Vitamin D supplementation in lesser amounts was harmful in any way.  In fact, they concluded just the opposite:

They also added that the results "do not alter the importance of correcting widespread vitamin D deficiency and insufficiency." On the other hand, the findings suggest that dose may be an important factor.

"There is no evidence for adverse effects of more frequent, lower-dose regimens, so daily, weekly, or monthly dosing with vitamin D₃ appears to be the best option for clinicians at this time," they concluded.

Looks to me like the study authors are supporting what Vitamin D3 proponents have been saying here all along.  I have seen no one here, nor have I seen any posted studies here, recommend anything approaching such a mega-dose of Vitamin D3.  In fact, what we have recommended would have to be considered frequent low-dose regimens when compared with the dose used in the study.

Whether or not the single mega-doses of Vitamin D3 might have had some ill effects, it should be pointed out that there are a world of vitamin, mineral and other supplements which can cause problems when consumed in such huge relative doses.  That many times the recommended daily intake of water itself would be fatal.

Thanks for posting yet another study telling us about the benefits of reasonable supplementation of Vitamin D3.