“Until this quality situation resolves to a meaningful extent, which may entail an entirely new method of regulation, any recommendations by health care practitioners to patients should generally be restricted to verified or tested products. … 

Cydney E. McQueen, PharmD, Associate Clinical Professor - Guest Editorial in the journal “Hospital Pharmacy” – March 2016
University of Missouri Kansas City – School of Pharmacy

“Should the FDA Regulate Vitamins, Herbs & Other Supplements” via HealthLine News - Supplements should contain exactly what they purport to contain. Currently, some products may not contain what the label claims.

Dr. Robert Wergin, President of the American Academy of Family Physicians
American Academy of Family Physicians