"The ITA represents reputable small businesses throughout the U.S. that already adhere to the highest professional standards including good manufacturing practices, " the group said.

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The FDA is very demanding and has a standard set of Good Manufacturing Practices to which all ingredient manufacturers as well vitamin or supplement manufacturers using these ingredients must comply to.

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In my opinion, the best solution would be to go with a brand that carries the seal of USP or NSF, two nonprofit organizations that certify that vitamins are contaminant free and made according to good manufacturing practices.

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That agency mainly acts to ensure that products are made according to good manufacturing practices, which include potency, cleanliness, and stability, that ingredients are generally safe, and that companies are not making unsubstantiated claims about curing or treating disease.

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