Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Low concentration of active indgredient

It's not mentioned in the product description but this product has a concentration of hypericin, the active chemical in St John's wort, of only 0.14%. Most St John's wort products have a concentration of 0.3%, and nearly all of the dosing guidelines I've found assume you're taking something standardized to 0.3%.Basically this means that if you take what should be an effective and safe dose of 900mg per day, you're getting less than half as much of the active ingredient as you might think. Except that I can't find any information on whether doubling the dose is safe, or if there are other factors to consider. Only Natural and Amazon are doing St John's wort users a major disservice by putting a non-standard product on the market with no warning or indication of the difference until the package arrives at your house.