Alex - I take a very large amount of supplements as various systemic support... ie, digestion, adrenal support, thyroid support, eye support, heart support, antioxidants, ...etc.
I follow the labeled directions. Most say to take with meals except in the case of amino acids where consuming on empty would allow maximum absorption and eliminate competition from any other aminos from food sources. I take Gamma E in the morning but take the tocotrienol form at night to avoid competition.
In the case of probiotics, I typically take at bedtime- on empty. Digestive support obviously is taken either before, during or after food.
Many nutrients require the acidic environment of the stomach to breakdown and metabolize so I tend to take the majority of mine either with a meal or right after a meal. Taken on empty, many supplements will cause stomach upset so long ago, I learned that unless contraindicated, taking with meals works better for me.
I try to use capsules, liquid or powders rather than tablets as often the coating on tablets doesn't break down efficiently and you lose the benefit and waste money.
Jackie