These seals are designed to give customers more information to help them decide which bottle to pick: 
   
  USP 
  • "Product was manufactured in a clean and professional environment; label reflects what is in the bottle; free of common heavy metals; pestisides; dissolves properly." 
  • Seal will be on about 40 products by the end of the year. 
   
  NSF International 
  • "Label reflects what is in the bottle; free of common contaminants; produced using good manufacturing practices." 
  • Seal will be on about 60 products that are available at nsf.org. 
   
  ConsumerLab.com 
  • "Label reflects contents; free of common contaminants; dissolves properly." 
  • About 400 participants have earned this seal, however no manufacturers are using it on their labels. Consumers can get a partial list for free at consumerlabs.com, or can pay a $17.95 yearly subscription for a list. The list does not contain products that failed its test. 
   
  Good Housekeeping 
  • "Label reflects the amount of active ingredient in bottle; clinical studies back up any health claims." 
  • Seal is on about six products and only companies advertising in Good Housekeeping can get the seal. 
   
  Source: The Wall Street Journal