The other other macronutrients


Here is the energy density of different food components, some of which were not previously discussed. it’s clear that we need to rethink the calculation of our calories based only on the three main macronutrients, protein, fat and carbohydrates,

Food component kJ/g kcal/g

Fat 37 9
Ethanol (drinking alcohol) 29 7
Proteins 17 4
Carbohydrates 17 4
Organic acids 13 3
Polyols (sugar alcohols, sweeteners) 10 2.4
Fiber 8 2


One question, is this Calories as in the amount of energy needed to raise the temp of 1 kilogram of water by 1 degree Celsius at sea level, (generally considered 4.184 kilojoules, though the exact amount depends on the starting temperature) or is it describing the Calories we can get out of each macro? I thought fiber was indigestible to us, so even though it contains potential energy, (Calories) these don’t add to our actual usable energy intake. Or am I wrong?

Also, I wonder about organic acids. Would oxalic acid really increase your practical calories or is it unusable? Would the degradation of phytic acid result in a small increase in the calories of grains?

And btw I don’t expect you to answer all these question @kthprog, I’m just putting them out there.


so fat has 9 cal per gram, alcohol 7 , protein and carbs 4. where did you get 37 , 29, 17 and 17 from?

and whos recipe includes nutritional alcohol?


If you read his post carefully, he stated that those numbers represent kilojoules per gram.


Attention to detail. Not a strength.