You asked "participating in clinical trials--a good one--but takes guts--what if the trial produces adverse results? Then what?" I feel 2025 clinical trials are a lot better managed than 1959 trials...when I was a "fluoride kid" being tested at the local low-income dental clinic in a settlement house! About 40 years ago, one of the authors of that study said the requirement was to "notify participant" but they didn't have to involve the FDA until they were seeking final approval!
Here is a snapshot of the current clinical trial protocol from
https://pmc.ncbi.nlm.nih.gov/articles/PMC9293739/
First, there is a pre-clinical phase, without human research subjects (90% of trials end here.) Clinical trials start SMALL and Phase I trials enroll fairly few, closely monitored volunteers (33% end here). Any serious adverse effect results in immediate cancellation of the trial. At the end of Phase I a detailed review of results and risks is submitted for review before Phase II can kick off.
Phase II is longer and involves more people, so it lets the researchers see a wider range of effects, positive and negative. Again, serious adverse effects end the trial. (50% of remaining trials end here).
Finally Phase III may come, with a broader cross-section, to see if it is safe enough to be released (40% of remaining trials end here).

Recent reports show that about 2% of trial drugs & treatments make it through all 4 phases, and then the FDA has the option of approving or denying and the company has the option of marketing or dropping.
By Phase I, it seems a pretty safe thing to try - you always have the option of dropping out.