B12高据说不是饮食引起的，而是与身体机能异常有关。两个links

http://www.livestrong.com/article/300753-what-are-the-causes-of-high-blood-levels-of-vitamin-b12/?

 

http://www.medicaldaily.com/high-levels-vitamin-b12-may-be-linked-increased-cancer-risk-263123