The main possible benefit of this charter, if it were to somehow become law, would be that it would allow people to have a greater range of choice in picking medical treatments for themselves. It would allow them more access to traditional and alternative medical treatments. This would increase personal freedom and might help to reduce the costs of health care.
The major danger of this is that it might encourage people to use treatments that really have no efficacy. This could well become a public health issue as people try to combat infectious diseases, for example, with herbal remedies that have not been scientifically proven to work. In addition, the idea that a person has the right to refuse any treatment might encourage people to stop having their children vaccinated. Once again, this could be a public health problem.