The Black Swan star wanted to swap her usual beauty routine for one that would make her body more baby-friendly.
The actress and her husband Benjamin Millepied welcomed their son Aleph into the world last year and the arrival has made her cut down on her morning make-up regime.
Portman spoke to America's OK! magazine, saying: "Everything needs to be a lot simpler now! And it needs to be faster because I have much less time for anything."
She also revealed that she is now more cautious of the sorts of body lotions and creams that she uses because her son is constantly putting his hands in his mouth.
Portman added: "I really want to make sure that everything I use doesn't have chemicals in it.
"It has to be really clean, because you know that your child ends up eating whatever you have on your skin or on your hands. And nail polish is the big thing too, because nail polish can be very toxic."