Want to do a double-blind study on whether St. John's Wort improves your mood? None of the bottles tested from Walmart, Target, GNC or Walgreens actually contained any St. John's Wort in 2015. That's despite all the reports years earlier about the same problem. There's little reason to believe things have improved or will improve so long as supplements remain largely unregulated.
That's a valid concern, and I agree that it's alarming. We will disclose where we are obtaining the L-Theanine from and provide a Certificate of Analysis.
Also, since this is a double blinded trial, if there are significant differences between placebo and real powders then that affirms that the powder was real.
I kinda wish the FDA had some certification to the effect that "this contains what it says it contains and its contents are no more likely to kill you than a peanut butter and jelly sandwich."
In the first link, all of those stores are places I'd never buy supplements from. Many stores sell supplements from brands I never see when I research what to take to fix some problem.
When I realized that, that was the end of ever considering buying supplements from almost all stores.
Whole Foods and similar types of stores are reliable. However, I still prefer researching and buying online. Analyzing comments, both good and bad, are very revealing and can sometimes give you an idea if it will work for you.
But now I just try to eat my veggies and so on. Diversification of food choices gives you a more solid spectrum of nutrients and some foods/nutrients amplify the effects of other nutrients.
Also, since this is a double blinded trial, if there are significant differences between placebo and real powders then that affirms that the powder was real.