RT Journal
A1 Bischoff-Ferrari HA, Willett WC, Wong JB, et al
T1 Relationship between bone, fracture, and exercise: The key role of vitamin d—reply
JF Archives of Internal Medicine
JO Archives of Internal Medicine
YR 2009
FD September 28
VO 169
IS 17
SP 1633
OP 1638
DO 10.1001/archinternmed.2009.323
UL http://dx.doi.org/10.1001/archinternmed.2009.323
AB 

			Annweiler and Beauchet suggest that the 20% nonvertebral fracture reduction with vitamin D supplementation at a dose greater than 400 IU/d may in part be explained by a direct benefit of vitamin D on muscle, resulting in fewer falls and thereby fewer fractures. The comment by Annweiler and Beauchet is supported by the presence of the vitamin D receptor in human muscle tissue1 and a rapid2- 3 and sustained4- 7 effect of vitamin D supplementation on falls from several trials. Thus, we agree—although falls were not assessed in our meta-analysis,8 supplementation likely resulted in reduced falls contributing to the observed fracture risk reduction.