Yet, Cameron uses epidemiological data to test a hypothesis that ionizing radiation stimulates the human immune system. For no obvious reason, he assumes that a stimulated (more active) immune system is a good thing. He suggests that a double blind study should be performed to explore this hypothesis further.

Over and above the logical issues here, are other problems with Cameron's idea:

(1) The function of the immune system is to identify and destroy foreign biological agents, such as bacteria. Unless there is some rationale for believing that ionizing radiation introduces foreign biological material, why should the hypothesis in question even be formulated, not to mention tested, on animals or humans? True, radiation can kill human cells, causing activation of components of the immune system during scavenging of the dead material, but why should destruction of functioning cells somehow be viewed as good?

(2) A highly active immune system in the absence of harmful biological agents has another, more common name: Allergy. Why should induction of allergy, even at a mild level, be considered a good feature of irradiation?

(3) There is some evidence that HIV causes AIDS and death by exhaustion of certain immune system components (T-cells). Why should hastening of any such exhaustion be a good thing? It is true that vaccination can activate the immune system and cause it to be programmed to defend against the biological agent of the vaccine; but, it is the programming, not the activation, which is beneficial in vaccination.

So, I read Cameron's hypothesis as being more or less equivalent to the statement that radiation improves life expectancy by making people sicker. He then proposes to administer a sub-sickening dose of radiation to help people live longer. A practitioner of homeopathy might view this as a stroke of genius, but I find it obnoxious.