The less confusing distinction would be between "slow (absorbed) calories" and "fast (absorbed) calories". That's what "glycemic index" and all that is all abou

The less confusing distinction would be between "slow (absorbed) calories" and "fast (absorbed) calories". That's what "glycemic index" and all that is all about. Most fibers are especially about this: they slow the absorbtion of sugars and other stuff, so they don't cause a spike in blood sugar concentration. You can even have basically pure carbs that are absorbed slowly and have a good glycemic profile (they are glucose polymers that take longer to break up into the glucose monomers they are made of). One of these is the modified starch that you can also get "naturally" by reheating some types of pasta, others are pretty weird chemical inventions that are not proven safe yet I think... You could eat just "pure slow carbs" and throw in some vitamin pills, essential fats, essential amino acids and antioxidants (they would all amount to like a small fist of pills a day I think) and be quite healthy I guess. Not sure why would anyone want to leave such a tasteless life though :) EDIT+: actually, scratch that, your liver might actually fail long term if you don't pass something more akin to "real food" through your gut at least occasionally, for probably complex reasons that amount to "the liver is a damn complex chemical plant that is expected to actually run continuously on all pathways, not to be left abandoned" ...I'm really looking forward for 10+ years results for the people living on that soylent thing only btw.