I’ve always searched for studies about impact of the ultra high frequencies (GHz i.e. billions as in bluetooth) on the brain and, more importantly, on the thyroid gland.

I’m not talking about ionizing radiation, cancer, etc. (sure, there’s plenty of studies on that; we know, there isn’t), but on how those high-frequencies in close proximity may affect metabolism or other normal functioning — no such thing existed during our evolution.

The reason I mention thyroid gland is that its disfunction may have very bad consequences (wiki it). Cognitive, psychological, etc.

Really would like to see studies about possible impact on that. Until then, just to be safe, I try not use any bluetooth headphones or use them wired (most have that option).