Charlize Theron has found being a parent has made her more ''aware'' of the dark side of humanity.

The 39-year-old actress - who adopted her two-year-old son Jackson as a baby - admits that while motherhood causes many women to adopt a more optimistic view of the world, she has become more ''aware'' than ever before.

The South African explained: ''People assume that once you have a child you will naturally veer away from the darkness, [but] I have found the opposite. ''Being a mother is the only thing I have experienced where the reality has surpassed my expectations of how great it would be, but the last thing I want to do now is to close my eyes to everything.

''My quest has always been to understand humanity in all its glory - its beauty and darkness - and I've become more enticed by that side of things since becoming a mother: I am very aware.''

The 'Monster' actress - who is in a relationship with Sean Penn - also admitted the intense nature of many of her movies means he will not be able to enjoy her work until later in life. She joked to You magazine: ''Other than my J'adore campaign, my son won't be able to see any of my work until he's about 53! I've made my peace with that.''