I'm not surprised, there does seem to be a pretty big overlap between people using healing crystals if you know what I mean, and people avoiding actually harmful chemicals.

Same principle as "why vegans live healthier". It's not because their diet is actually healthier per-se, same as healing crystals do not work. But a vegan person, same as a person using healing crystals is likely to be a strongly biased sample of the population. They tend to be more aware of their lives, their bodies and the consequences of what they do to their bodies. And that, as a net effect, yields a healthier lifestyle on average.

But an unhealthy person will never get healthy by eating vegan, same as they won't get healthy by using healing crystals. It only works if you embrace the lifestyle and accept it mentally and become a "biased sample" yourself.