Margaret Haywood said she gave her actions a lot of thought
Fresh calls to protect whistle-blowers in the NHS will be made on Panorama after two high-profile cases.
This month, Margaret Haywood was struck off the nursing register after secretly filming hospital patients in Brighton.
In March, the Healthcare Commission revealed "appalling conditions" at Mid Staffordshire NHS Trust.
Cannock Chase MP Tony Wright wants the government to do more to protect whistle-blowers. The Department of Health said they were protected by law.
The Labour MP said: "The whole point of introducing whistle-blower provisions was that someone had got somewhere to go so they could raise these concerns quite properly without threatening their job, without damaging their career and indeed without having to go to the media."
Ms Haywood, who said she acted to make people aware of what was happening after complaints to her ward manager went unheeded, was struck off by the Nursing and Midwifery Council for breaching patient confidentiality.
'Lot of thought'
In an interview to be shown on Panorama on Monday, the 58-year-old said: "There was no other way of doing it really.
"I didn't take the decision lightly - I did look into it, I did give it an awful lot of thought and I knew, you know, that my position would be compromised by doing it.
"But I think the public needed to be aware of what was going on on the ward.
"They're putting their relatives in there believing them to be cared for and that wasn't happening."
Ms Haywood recorded conditions of elderly patients at the Royal Sussex County Hospital for a Panorama documentary, Undercover Nurse, which was broadcast in July 2005.
Footage from her filming showed examples of neglect including an elderly patient sitting in clothes he had soiled the night before.
More than 14,000 people signed a petition set up by the Royal College of Nursing in support of her after she was struck off, within a week of it going live.
Dr Richard Taylor, who became an independent MP for Wyre Forest following a campaign against the downgrading of Kidderminster Hospital, in Worcestershire, said he believed a culture of fear still existed in the NHS.
He said: "I think the whistleblowing policies we've got at the moment are absolutely inadequate or else people wouldn't be coming to me as an MP instead of going to their immediate bosses."
Panorama: Who'd be a NHS Whistleblower, 27 April on BBC One at 2030 BST
Ms Haywood said complaints to her ward manager went unheeded
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