QualitySettings.masterTextureLimit Causes Huge Amount of lag

Hi everyone, I tried setting QualitySettings.masterTextureLimit to 2 by doing the following below. For some reason it causes a huge amount of lag. Any idea how to fix this?

void update(){
QualitySettings.masterTextureLimit = 2;

Changing this affects all loaded textures, so it causes a huge hitch. Don’t do this every frame.