Trying to find a cause for my sons[15] bradycardia 40 -45 . can vit d deficiency cause it? his is 10.

Is a Slow Heart OK?: Vitamin d deficiency causing a slow heart rate in your son is unlikely. If your son is a highly conditioned athelete, it is not uncommon to have slow resting heart rates. The "athlete's heart" is quite commonly in the 40's. Please see your doctor to make sure there is no medical condition causing the slow heart rate. Study link: http://www.Ehealthme.Com/cs/vitamin+d+deficiency/bradycardia.

Many possible causes: I would recommend that your son see a pediatric cardiologist for this issue, if he has not already. Vit d deficiency is not known to cause this problem, but many people have this issue and need supplementation. If your son only has this bradycardia for a portion of the day, and otherwise has a normal rhythm and heart rate response to exercise, no treatment is probably necessary.