Yet another instance when taking something that’s good in small doses becomes harmful if taken in a extra-large doses.
This time, it’s everyone’s pet vitamin these days, namely Vitamin D.
According to a 3-year-long study from the University of Calgary, post-menopausal “women who received 400 IU of vitamin D daily” (that’s a pretty standard small dose) had a small loss of bone density (BMD) in the radius (1.8% loss).
In contrast, women who got 4,000 IU per day had a 3.8% loss in total BMD.
If you believe in Vitamin D, probably much wiser to take “normal” doses than high ones.
Same goes for most medical interventions, of course.