In May 2010 issue of AARP ( not available on-line)
Click here for ABC News May 3 2010
Know your numbers - From Dr. Oz via AARP/ABC
Dr. Oz elsewhere keeps to the obsolete government edict of not taking more than 2000 IU - which make is virtually impossible for a person to achieve 50 ng/ml
many people require >3,000 IU to achieve 50 ng/ml
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