During a nuclear explosion, one byproduct is radioactive iodine (I-131). This can bioaccumulate in the thyroid and damage it or lead to thyroid cancer. One way to prevent that is to swamp the body with non-radioactive iodine (mostly I-127) so that you don’t absorb the radioactive version.
Sentient111 t1_is4wsr9 wrote
Reply to Why do people take iodine pills for radiation exposure? by Furrypocketpussy
During a nuclear explosion, one byproduct is radioactive iodine (I-131). This can bioaccumulate in the thyroid and damage it or lead to thyroid cancer. One way to prevent that is to swamp the body with non-radioactive iodine (mostly I-127) so that you don’t absorb the radioactive version.