What is tourmaline? Is it harmful?

The custom of tourmaline (called tourmaline)

What? Tomalin gives herself heat to protect her waist. I bought three for my parents. It's totally useless

The small spots on the white cloth of the belt are not tourmaline, but rubber particles, which are infiltrated with some chemical capsaicin. There are no nano biomaterials, only rubber particles and a piece of cloth, and the cost is below 1 yuan.

There is nothing that continuously releases far infrared rays, no micro-current, no self-heating. If someone invents something that can produce these things, he will definitely not make money by doing it. The Nobel Prize is waiting for him! This is the same as the scam of changing water into oil many years ago, which violates the basic principles of physics.

A doctor of medicine told me that natural capsaicin itself has certain medicinal value, but it must be chemically synthesized capsaicin, otherwise it would be impossible to integrate it into rubber particles and have a spicy feeling for such a long time. Chemical capsaicin has no medicinal value except temporary pungent feeling. Long-term use of chemical substances will definitely decompose and fail, and the decomposed substances are likely to be harmful to human body. However, due to the small amount and slow process, human body cannot detect it.