The higher the heat, the worse it is.
Not necessarily. A slightly damaged molecule is unlikely to be immediately recognized as such by the immune system, while a completely wrecked one would be discarded straight away. Thus the first one could induce a lot more troubles in the metabolism.
This seem to be confirmed by the
experiment on mice done by GCB & al in the 60’s :
Les conclusions générales de cette expérience sont les suivantes :
a/ Le groupe le plus catastrophique est le groupe "diététique". Avec
des dénaturations supposées minimes, cette alimentation se veut
pourtant « hypotoxique » (= faiblement toxique). Elle comprend
notamment du blé bio cuit à des températures inférieures à 100°. Des
lots de souris sont alimentés avec du blé et autres aliments "bio"
chauffés à 50°, d'autres avec des aliments chauffés à 60°, d'autres à
70° et ainsi de suite. Certaines souris deviennent très maigres,
tandis que d'autres grossissent énormément. Les souris se mangent
entre elles ou meurent prématurément, d'elles-mêmes. Il n'y a pas
besoin de les tuer pour la dissection.
b/ Les cages cuites :
Curieusement les résultats sont moins mauvais qu'avec des
dénaturations « douces ». Les souris sont nourries avec des patates
cuites, de la viande cuite, du pain… Elles se mangent aussi entre
elles. Mais ce qu'il faut retenir c'est qu'il y a globalement une
amélioration par rapport à l'alimentation diététique.
Rough translation:
The general conclusions from this experiment are:a / The most catastrophic group is the group "healthy diet". With assumed minimal processing, this diet aims to be "hypotoxic" (= only slightly toxic). It includes organic wheat cooked at temperatures below 100 ° C. Some mice groups were fed with wheat and other "organic" foods heated to 50 °, other groups with food heated to 60 ° C, other groups with food heated 70 ° C and so on. Some mice become very skinny, while others grow enormously obese. The mice eat each others or die prematurely, spontaneously. There is no need to kill them for dissection.
b / Cages cooked:
Curiously the results are less bad than with "light" cooking. Mice were cooked fed potatoes , cooked meat, bread... They also eat each other. But what we must remember is that there is an overall improvement from the “healthy diet”.
Temperatures up to 118 F have been recorded inside the human body, so I imagine anything up to that temperature is not extremely damaging, at least not to meat/fish. Fruit, and especially honey, are going have some damage, mainly honey.
That is 48° C. I don’t know from where you got this number but let’s admit it’s true. Ok, wide scale damage to organic molecules start probably a little over that; according to an oral report I heard, the calf fed with milk heated at 55° C are faring very badly, being sick and unable to reach a normal adult state.
By limiting our intakes to food not heated over 40° C, we hopefully have a slight safety margin.
When I say lightly steamed, I really mean that the inside of the food is only raised to around 105 F or so. The outside can be a little warmer, with relatively little damage.
41° C inside… but this “little damage” of the outside is precisely what should be avoided. Completely carbonize your food would certainly be less hazardous since
pure carbon has extremely low toxicity to humans.