James Collier explained this a bit in another thread a month or so ago:
The US and UK formulas for Huel Ready-to-drink are exactly the same and made, currently, in the same place. What is in there is tapioca starch. However, US labelling requirements mean we have to label it as ‘Tapioca Maltodextrin’, whereas in the EU we can label as ‘Tapioca Starch’. It is not maltodextrin the the same form as normal maltodextrin and is not produced in the same way. I don’t know why US labelling requires it to be labelled this way and I have asked an expert and she didn’t know either. it’s frustrating.
Either way, we have had the GI of Huel Ready-to-drink tested and it’s low GI at 25. Read more here .
The glycemic index of the overall drink it is also affected by the amount of carbohydrates, fats and proteins. Particularly fats will slow down the digestion of carbohydrates, making the overall glycemic index of the drink it’s lower. https://academic.oup.com/jn/article/136/10/2506/4746688
We conclude that, across the range of 0–30 g, protein and fat reduced glycemic responses independently from each other in a linear, dose-dependent fashion, with protein having ∼3-times the effect of fat.
I.e. even if Huel had some maltodextrin (which is not the case) with the GI of 80; the drink could still have the a GI of 30ish (Soylent for instance).