A self-regulating heater is provided by placing ferrite-type body member, which is highly lossy when exposed to a high frequency magnetic field and has a predetermined Curie temperature, on or around a central conductor which is connected or is adapted to be connected to a power source which provides high frequency alternating current to the conductor. The current passing through the central conductor produces a magnetic field around the conductor, which causes the ferrite-type body to be heated by internal losses to its Curie temperature. The heater self-regulates at the Curie temperature of the ferrite-type body. The power source is preferably a constant current, impedance matched power source. The ferrite-type body member can be ferromagnetic or ferrimagnetic. The ferrite-type body is preferably ferrimagnetic, such as ferrite beads, rings, and the like, which heat by hysteresis losses.