In accordance to modern science, one would never expect any deviation from natural distribution of isotopes for a given chemical element. It does not matter which object of nature this element belongs to, and where it is in our universe.
We have discovered that in fact changes of isotope concentrations in favor of heavier isotopes is a feature of abnormalities in various life forms from plants to mammals. Prevalence of heavy or light isotopes in live organisms can be considered as signatures for old and sick, and young and healthy correspondently. We can see this on the example of Zinc isotopes distribution in “young”, “old”, cancer affected, and normal tissues of mammals, in the internal healthy rings, the fungus called “chaga” and the surrounding bark of the host birch tree.