Sugars may not be "toxic" per se but dietary intake of sugar or carbohydrate is certainly not essential for human life. Your liver will create glucose when need

Sugars may not be "toxic" per se but dietary intake of sugar or carbohydrate is certainly not essential for human life. Your liver will create glucose when needed and your brain will happily burn ketone bodies when it isn't available. You can easily survive on a diet of mostly animal fat.