The word “systemic” means body wide. Systemic enzymes are those that operate not just for digestion but throughout your body in every system and organ. But let’s take first things first, what is an enzyme? An enzyme is a biocatalyst - something that makes something else work or work faster. Chemical reactions are generally slow things, enzymes speed them up. Without enzymes the chemical reactions that make up our life would be too slow for life as we know it.
Enzymes are protein molecules that act as organic catalysts that allow many of the different chemical reactions that occur in the body every day in order to maintain homeostasis, without which the body can't function. A catalyst is a chemical that is involved in a chemical reaction, but is not changed by the reaction.