So, when you take a bunch of folic acid, this leads to the DHFR enzyme being overloaded and a lot of unmetabolized folic acid is left floating around.

所以，当你服用大量合成叶酸时，就会导致二氢叶酸还原酶在体内超负荷工作，并且大量未被代谢掉的合成叶酸会在体内滞留。