Fame Pictures

Jennifer Aniston recently collapsed on the set of her upcoming romantic comedy, The Baster.

According to sources for Transworld News, an exhausted Jen had been working 14 hour days shooting scenes on-location in Manhattan for nearly a week when she began feeling faint one afternoon last month.

“She frantically yelled out, ‘I need a break!’ She said she felt dizzy and light-headed. She’s usually so calm,” says an on-set informant. “She rushed to her trailer to rest and collect herself, but she lost her balance and nearly keeled over. The collapse really shook Jen up. It was a wake-up call that she needs to slow down.”

A second insider claims Jennifer’s troubled love life — or lack thereof — has finally taken a toll on the actress’ health. “She’s upset that she’s 40 and all alone. Her love life is definitely causing her sleepless nights and stress.”