Jessica Alba has recalled her worst acting moment, declaring it "awful".

The Honest founder revealed her most hated movie scene, confessing she had "dreaded" shooting a moment in which her Fantastic Four character, Sue Storm, was forced to strip naked to conduct a rescue.

"I thought that was awful," Jessica, 44, recalled during a career talk at the Red Sea Film Festival in Jeddah, Saudi Arabia.

"It was very humiliating in real life. I grew up with a pretty conservative family, and I am a pretty modest person. I dreaded that scene for weeks. I have a lot of whiplash from those days."

However, Jessica said, overall she was happy to have played Sue - otherwise known as The Invisible Woman - as she considered the superhero character a strong female role model.

"She was a woman I looked up to," the Honey star reflected. "She was very maternal and very kind, but also not a pushover; she spoke her mind."

Jessica added she was particularly proud to have played a tenacious female character early in her career, given Fantastic Four's 2005 release date.

"She had a great moral compass. No matter who you are, you can look up to her," the actress and entrepreneur said. "Oftentimes, the women in these stories need to be saved by a guy or the villain, the problem in the story. This was back then. It's different now."