ANy amount of sugar or foreign substance in your fuel tank can do damage, and if it is suspected that there is some in your tank then you should have the tank removed and flushed out, and a new fuel inlet strainer and inline fuel filter installed before driving the vehicle at all.
Sugar is granular and will cause damage to a fuel pump if ingested; it will grind up the internal rotors in the electric pump.
If enough is pumped upstream before the pump wears out, it can clog a fuel filter, clog injectors, amd if enough makes it's way through the injectors will tend to crystallize on the intake valves causing the valves to stick in their guides. This can cause valves to not close completely, resulting in valve/ piston interference (bent valves/ damaged heads/ damaged pistons.... major internal engine damage).
I hope this is helpful to you; if so, an accept would be most appreciated! thanks!