Christina Hendricks is ''fascinated'' by getting older.

The 'Mad Men' actress - who turns 40 this month - isn't worried about her advancing years but has noticed she is changing quicker than ever.

She said: ''I'm fascinated by getting older. I can't believe how resilient the human body is, though now I'm older, I notice everything changing that bit quicker.''

The flame-haired beauty added she doesn't feel like ageing will have any effect on her career.

She said: ''Well, I'm never going to be up for the role of a 20 year old and vice versa.

''The role is the role and there are plenty of great ones out there.''

And despite seven seasons as 'Mad Men's Joan Harris, Christina isn't concerned about being typecast.

She said: '''Mad Men' is such a specific show and when you take us out of the 1960s we look very different.''

Because she is noticing physical changes, the 'Lost River' actress - who is married to actor Geoffrey Arend- does take some precautions to look after herself.

She told Red magazine: ''I wear sunscreen every day and I really watch my skin so I can treat it accordingly.

''When I go out, I wear a bit of tinted moisturiser and always some cream blush, as it really wakes me up and makes me look fresh.''