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There are a few differences between the Vegan AminoXXXL and regular AminoXXXL. The Leucine in the regular AminoXXXL is derived from duck feathers and the other 7 amino acids from microbial fermentation while the Vegan AminoXXXL uses microbial fermentation for all 8 amino acids. There is a significant cost saving when deriving the Leucine from duck feathers, hence the increased cost of the vegan formula.
Other differences are the sweeteners and flavor package which are all natural in the Vegan AminoXXXL. We use Stevia and Raw Cane Sugar in the Vegan AminoXXXL and thus the reason the higher calorie count per serving (70 calories).