The title of this article does not reflect the findings of the research paper. First, the cited study was very complex and did not investigate cause and effect between gene loci and metabolic outcome. The paper did contain lots of interesting conjecture. One such conjecture was that how we metabolize iron as we age can affect longevity. Importantly, iron metabolism and homeostasis are highly complex, and iron levels per se do not necessarily reflect that complexity ( except in certain diseases). The point of the research paper was to communicate findings and suggest possible targets for further research. It did not identify iron levels as an aging factor.