This is the core mechanistic premise of Bircher-Benner’s system, stated in his own title Food science for all and a new sunlight theory of nutrition (1928) and elaborated in The essential nature and organisation of food energy (1939). The claim is mechanism-only: it posits a special living sunlight energy carried by raw plant food and infers nutritional and curative value from it, without a measured endpoint. It is classified as refuted because the additional vital solar charge it requires (beyond the ordinary chemical energy plants store by photosynthesis and animals release by metabolism) was never demonstrated and has no place in established nutritional science, which accounts for nutrition by energy and specific nutrients rather than by stored sunlight that cooking destroys. Contemporary official medicine did not recognise Bircher-Benner’s nutrition theory (swissinfo.ch 2025), and historians of medicine read it as a health-reform moral physiology rather than as validated nutritional science (Meyer-Renschhausen and Wirz, Medical History 1999).