Isomaltulose is the main sugar in Soylent version 1.7 and above. It's interesting because it's absorbed slowly by the gut instead of quickly like most sugars. The glycemic index is reported to be around 32 for Isomaltose while for sugar it's 100. This slow release might explain the energy boost of Soylent without the crash you would get from higher glycemic index sugars. Additionally it doesn't seem to raise blood insulin as much as other sources of carbs, so overall it is interesting. Whether or not it is safe long term is questionable.