This is the most commonly raised point of view that many people questioned that hydrogen medicine is a "pseudoscience". As an emerging discipline that has not been developed for a long time, it is normal to be questioned. Why has hydrogen not been used in hospitals? There are two main reasons. First, it is true that hydrogen medicine has not been developed for a long time, and there is still a lack of rigorous large-sample clinical studies to determine the actual effect on certain diseases, awareness is still very low, and it takes time to understand and popularize; another reason is that clinical application is not determined by simple medical research, a clinical treatment method can only be approved by the National Food and Drug Administration (such as the US FDA) Only then can it be used in the clinic. This approved method is defined as qualified clinical drugs and medical devices. Obtaining this standard requires R&D equipment manufacturers to submit medical device registration applications to national institutions, pay a large amount of funds for clinical research, and then obtain medical qualifications through a long application path, all of these require a long time. Of course, nothing does not mean that there will not be in the future. There are already many institutions and companies in China and Japan working hard to do this, especially the hydrogen inhalation machine, which is also the most promising method of hydrogen therapy in the future. Therefore, it is only temporary that hydrogen medicine has not entered the clinic, and it is the goal of current efforts to strive for early clinical application.