Have you ever noticed how many people take advice so much to heart and trust the source so much, that they will continue to follow the advice despite strong evidence that it isn't any good?
I've noticed that about quite a few things. Lots of natural supplements make quasi-scientifically based claims about what this or that supplement or herb will do for you. A friend of mine has some struggles with anxiety. I've been there. Anxiety has been a major problem in my life at different times, so I know how desperately she wanted to find a solution.
Of course, she wasn't willing to try any of the solutions that real scientific research has shown to be effective (yes, there are some and they include pharmaceutical agents, mindfulness meditation, and exercise). She claimed pharmaceutical agents do more for the pharmaceutical company than you, and because they aren't from natural sources they must be harmful (Yes, I pointed out that lots of natural chemicals are actually quite harmful, even poisonous), and she just didn't have time to meditate or exercise.
What she did do was follow the advice of a supposed expert (a chiropractor), who had her taking some phytochemical substances that are marketed as effective treatments for her problems. Meanwhile, she clearly still suffered from the problems and just saw that as just further evidence she needed the substance, so she kept paying the chiropractor for the stuff, and kept being anxious, getting only an occasional placebo effect for a little while after she took it (maybe). Maybe the placebo effect is enough to satisfy some folks, but in my view, if a biochemical effect is being claimed, there should be one.
Another woman, was taking a substance that was supposed to prevent breast cancer, which runs in her family. It was said that this substance would practically eliminate her risk of cancer... What happened? She was diagnosed with breast cancer after taking the stuff for two years. What was her response? Oh, she should have been taking much more of the stuff!
My point? Most claims made about substances marketed as nutraceuticals or supplements or herbal remedies have little to now effect when they are really put to the test. Those who want to believe the conspiracy theories about pharmaceutical companies and physicians being in bed together and endangering their health with drugs, but fail to see the conspiracy in efforts to separate them from their dollars by selling them ineffective treatments based on quasi-scientific "clinical studies," that actually qualify neither as clinical or study, will likely go on believing what they want, despite the evidence.
That first friend's chiropractor... Well, he makes money for selling the supplements he sells in his practice. He even receives gifts from the companies he buys them from because he's such a good customer for them. The same thing happens with physicians and drug companies, to be sure, but honestly... I don't see a difference. Both are trying to sell chemicals to treat problems that can probably best be prevented by ordinary, healthy living (in the mental and physical senses).