This is the mechanistic premise of Hufeland’s macrobiotics, set out in Die Kunst, das menschliche Leben zu verlängern (1797). The Erasmus Wilson English edition states it in its chapter structure: an “Inquiry into the nature of the vital power, and the duration of life in general” is followed by the proposition that “vital consumption” is the “inseparable consequence of vital operation” and so fixes the “term of life.” The claim is mechanism-only: it posits a vital force and infers the term of life from its consumption, without any measured endpoint. It is classified as refuted because the vitalist framework it depends on, the doctrine of a special life-principle not reducible to physics and chemistry, lost standing through the 19th and early 20th centuries as mechanistic and physico-chemical physiology accounted for more and more vital phenomena (De Klerk, Acta Biotheoretica 1979; Encyclopaedia Britannica, “Vitalism”), and has no place in mainstream modern biology. No discrete, measurable vital force of the kind the claim requires has been shown to exist or to govern lifespan.