AceShowbiz - Actress Shailene Woodley ate no more than 350 calories per day while shooting her new survival drama "Adrift".

The star shot much of the movie at sea and admits the filming experience was tough on her body, because her seasickness was amplified by her shockingly low-fat diet.

"I can't sleep when I'm hungry, so I would have a glass of wine (every night) to basically pass the f**k out," she tells U.K. newspaper The Times. "For the last two weeks (of the shoot) I had a can of salmon, some steamed broccoli and two egg yolks every day."

Shailene plays Tami Oldham in the true life story of her 41-day survival at sea in 1983 with then-fiance Richard Sharp, portrayed by Sam Claflin, and reveals she leaned heavily on her co-star to cope with the challenges of the intense film shoot.

"I don't know that I could do it without Sam," she confessed. "We both really were there for one another in our moments of extreme exhaustion and hunger."

Woodley previously revealed she and Claflin bonded with the rest of the Adrift crew as filming became a physical hardship, admitting many scenes didn't require an awful lot of acting: "What the audience sees in that scene (when a hurricane is approaching) is a look of nervousness, but it's really Sam and I trying not puke when the cameras are rolling," she told USA Today. "It's like, 'Keep it together'. That's pure anxiety."

"When you're stuck on a boat with 15 people every single day, you're all dealing with things like the toilets breaking and everyone just having to jump in the ocean to use the bathroom," Shailene added. "There's a lot of discomfort, there's a lot of bodily smells. And a lot of humour. That's the glue that keeps everyone together."