The marketplace is a dangerous place whether you are at your pharmacy or your health food store. Buyer must be aware. A company that values its reputation is a good start. A friend who ran a health food store once told me that Jarrow is great. It is still owned by its founder and Mr. Jarrow has a reputation roughly equal to a fire breathing dragon where quality control is concerned. If a supplier signs a contract to provide quality "A" and is found to have sent quality "B" instead to save a little money, Jarrow is not content to just sue for damages. He has made it clear that his lawyers are there to destroy any supplier found to be trying to pull anything. As a result, his products are among the best.