does white sugar have a shelf life? i have had a sealed container of white sugar for about 5 years now, we have been using it slowly, but is it safe/healthy to continue using it because of its age? or should i replace it?
Various references, including this one from Lantic sugar note the shelf-life of granulated white sugar as indefinite or effectively forever.

Presuming, likely, that it is stored as you note in a sealed container.