Vitamin A plays an important role in supporting the immune system, regulating gene function and producing health red blood cells. Most importantly perhaps, it is crucial to the maintenance of good eyesight. Indeed one of the hallmarks of vitamin A deficiency is night blindness. Night blindness is defined as a reduced ability to see things in low light conditions. This occurs because the nerve impulses in our brain that interpret visual information depend on vitamin A to function properly. Below are the 10 best vitamin A supplements for 2018.