When his father’s attempts to beat the gay feelings out of him failed, 11-year-old Sam Brinton was sent for conversion therapy.

“I was told I was the only gay left in the world, that the government had killed all the gay children, that I had Aids, that God hated me – a horrifying battery of lies which I had no reason not to believe because these were the people that were supposed to be helping me,” Brinton said.

Then came the physical torture: forcing his hands into ice while showing him pictures of men touching men, wrapping his hands in coils that heated up painfully when he saw images of men hugging, showing him gay porn and giving him electric shocks.

Several suicide attempts later, Brinton, the son of Southern Baptist missionaries, realised he had only one viable option if he wanted to carry on living.

“In the end I had to lie and say I was cured just to get out of it,” he said.

Brinton doubts he will ever completely be free of the trauma. “I’m definitely still processing. The hard part is because it happened long ago, a lot of it is mentally associated into my cognition. Therefore, every single time I shake a man’s hand or get a hug, I’ll have a small amount of shock hit me.

I will probably bear the mental torture marks of conversion therapy for the rest of my life Sam Brinton

“It’s not that bad anymore, but I will probably bear the mental torture marks of conversion therapy for the rest of my life.

“The hardest part was that I was trying so hard to change. Every night I was praying with every ounce of my body, trying to figure out a way to actually change so that the pain would stop. You definitely think that something’s wrong with you and that if you try hard enough you can beat it.”

Like many other activists, Brinton was delighted when the Obama administration issued a statement on Wednesday night calling for a ban on conversion, or so-called reparative, therapy on minors. The White House’s action came in response to a petition inspired by the death of a transgender teenager from Ohio, Leelah Alcorn, who stepped in front of a tractor-trailer one night last December. Her suicide note referred to visits to Christian therapists who told her she was “selfish and wrong”.

Conversion therapies that try to turn gay people straight have been widely discredited. According to the American Psychological Association, “the most important fact about these ‘therapies’ is that they are based on a view of homosexuality that has been rejected by all the major mental health professions” – that it is abnormal, unnatural, and a mental illness that can be corrected.

New Jersey, California and the District of Columbia have banned the practice on young people, yet it remains widespread and attempts to make it illegal in numerous states have floundered, most recently in Colorado, just a few hours before the White House took a stance.

In 2012, four gay men launched an ongoing lawsuit against a conversion therapy centre in New Jersey, claiming they had been put through humiliating and harmful exercises such as stripping naked in front of a mirror and holding their penises, beating images of their mothers and squeezing two oranges that represented testicles.

In 2012 Michael Ferguson, centre, was one of the four gay men making allegations against a New Jersey centre that did conversion therapy. Photograph: Richard Drew/AP

Samantha Ames, staff attorney at the National Center for Lesbian Rights (NCLR), said research indicated that as many as a third of LGBT people have undergone some form of conversion therapy – from seeing licensed practitioners, talking with church leaders or visiting religious camps to extreme versions which can include nausea-inducing drugs, needles in fingers and “orgasmic reconditioning”.

‘Obviously our president doesn’t know anything’

David Pickup, a licensed family and marriage therapist who works in Dallas and Los Angeles, said he and others offer a legitimate service and will lobby against attempts to outlaw it. He said the reputation of reparative therapy has been tarnished by “quacks” offering “junk” such as attempts to “pray away the gay” and shock tactics.

“Obviously, our president doesn’t know anything, or very little, about the nature of homosexuality for some individuals, knows very little about the scientific and anecdotal evidence that indicates that sexuality is changeable and that it’s not something that’s naturally inborn,” he said.

Scientific and anecdotal evidence indicates sexuality is changeable and not something that’s naturally inborn David Pickup

“People who are gay don’t have a disease, they are not mentally ill, nothing like that, but the research shows that sexuality tends to be rather fluid and especially for individuals who during childhood have been sexually abused by same-sex pedophiles, whose sexual feelings have come up because of these incidences. It’s an egregious error to say those little kids who are grieving and confused can’t get therapy to reduce or eliminate their same-sex attractions.”

Last year, the NCLR launched a campaign, Born Perfect, which aims to have the practice banned across the US within five years.

“This industry is absolutely not going down without a fight. They are as strong and as determined and as destructive as ever,” Ames said. “This is not just like any other LGBT issue; this is really about the health and safety of our children.

“What we hear time and time again from survivors is that, as barbaric as these techniques can get, it is not the techniques themselves that are most damaging. What is most damaging across the board is the purpose of those techniques – to change the core identity of who a person is.”

‘It was just killing me’

When Bryan Christopher took an elevator to the top of the Empire State Building 15 years ago, he was not looking forward to admiring the view. He was thinking about throwing himself off. Born in 1970 and brought up by conservative parents in Waco, Texas, he spent more than a decade hiding his sexuality and undergoing conversion therapy.

“Growing up in the 80s and 90s, there weren’t any voices around me that were saying it was OK to be gay,” he said. “My crusade to change went through many different twists and turns and it ultimately did lead me to ex-gay conversion therapy.

“At UCLA I joined the fraternity, thinking that would set me straight, and I worked as a butler for Hugh Hefner at the Playboy mansion, thinking that would set me straight. Ultimately it came to the point where I realised: if I’m going to change, then I need a miracle and I need to seek out God, and really do everything I can to heal what I’ve been taught is broken. To fix it.”

In his 20s, Christopher took anxiety medication and sought help from a psychotherapist and Christian mentors.

“The turning point was right after college when I called a Christian suicidal hotline and put myself into a psychiatric hospital for 72 hours,” he said. “I was 24 and I hadn’t changed and was strangely in love with a fraternity brother who ended up becoming a high-profile basketball player at UCLA.

My heart was wanting one thing and my mind and all the voices around me were telling me no, it’s a sin, it’s a sickness Bryan Christopher

“It was just killing me. My heart was wanting one thing and my mind and all the voices around me were telling me no, it’s a sin, it’s a sickness. Even with a degree in psychology from UCLA, where I learned that it’s just a normal variation in human sexuality, I still discarded all of the medical conclusions and I still felt I could change.”

Christopher ended up seeing an “ex-gay” California-based Christian reparative therapist, who told him that homosexuality had root causes – perhaps a weak father and a strong mother, rejection by classmates, or liking art but not sports.

“None of that was true for me,” Christopher said. “I had great parents, I had friends, I was never the excluded one, I was popular in high school. I led a very heterosexual life. You don’t get more heterosexual than the Playboy mansion and a fraternity.

“They used the disease model of alcoholism to draw parallels. So when I asked him, I said point blank: ‘Do you still have gay inclinations or desires?’ he said that he monitors the events in his life, where he goes, who he’s around, so he never puts himself in a situation where he’d be tempted, much like an alcoholic doesn’t go to a bar.”

Christopher finally realised that his struggle was futile and self-destructive. “It’s a form of soul torture, really, especially when you do it as long as I did. And no one forced me into it. I went into it willingly because I was a true believer. I thought this was something that could be cured.”

He now lives in Minnesota with his partner, works in real estate and has written a memoir, Hiding from Myself.

‘If you think about it, we’re double-trapped’

Brinton, now 27, works for a think tank in Washington, advising politicians on nuclear issues. “Many of my fellow survivors of conversion therapy have died of suicide,” he said. “I know of dozens that have died and it’s horrifying.

“If you think about it, we’re double-trapped. We can’t got back to therapists because they’re the ones who ‘hurt’ us in the first place. So our mental health access is extremely limited.”

Last year, Texas Republicans adopted a platform backing reparative therapy “for those patients seeking healing and wholeness from their homosexual lifestyle” and stating no laws to prohibit it should be introduced.

This year, Celia Israel, an openly lesbian Democratic state representative in the Austin area, introduced a bill to ban reparative therapy for minors. She does not expect her bill to become law, but wanted to make a point.

“I thought it was important to introduce the bill to make a statement that this should not be accepted practice any more,” she said. “They don’t need to be ‘fixed’; they just need to be loved.”