Vitamin A Toxicity

It's easy to get enough vitamin A from whole foods:  animal source retinal. 
Supplements are not necessary or as effective as food, in fact, they can be harmful.

The problem is vitamin A toxicity as a result of light exposures to the eyes and skin. 
Blue light from artifical light dominant in the blue spectrum, or all blue like LED. 
Lack of natural red light instead of the blue light. 

Artificial blue light breaks retinal away from melanopsin as a cofactor for utilization. 
Melanopsin is bound to Vitamin A (retinal) by a loose covalent bond and when blue light dissociates the bond retinal is freed.  
Melanopsin are pigments in the skin that are photoreceptors that the sun uses to regulate our body chemistry. 

Get more full spectrum sun in the eyes and skin. 
Block blue and dim artificial exposures in general with orange screen protection and dimmers. 
Read my sections on Electro Toxic and Sun......

Don't get lost with extreme Vitamin A avoidance diets and detox.