Hilary Swank at Conde Nast Media Group's 5th Anniversary of Fashion Rocks at Radio City Music Hall - Arrivals. New York City, USA - 05.09.08

The actress donated her own locks after having her hair chopped off to play aviator Amelia Earheart in a new movie.

And now she's backing the Beautiful Lengths campaign to encourage other women to follow suit - and help give hair back to those who lose it when they undergo chemotherapy.

Swank says, "One in three women are diagnosed with cancer in their lifetimes. A lot of my family members have had their lives devastated by cancer.

"You just need to have eight inches (of hair) to donate."

Source: WENN