People use “frequency” to describe many different ideas, from measurable physical rhythms to claims about wellness devices and healing. Those ideas do not all have the same scientific status.
The body does have measurable rhythms and signals, including brain activity, heart rhythm and electrical activity in nerves and muscles. Claims that a particular frequency can diagnose illness or treat gut, immune or metabolic conditions need reliable evidence for that specific use.
Explore emerging ideas with curiosity and clear labels for what is established, uncertain or speculative. An interesting hypothesis is not the same as a proven health treatment.