A charity employing the controversial Neuro-linguistic programming (NLP) in mental health therapy has been asked to stop after war veterans said they felt worse, and even suicidal, after attending therapy sessions. Healing the Wounds in Porthcawl, Wales, is a charity that claims this type of treatment is effective in assisting armed forces veterans with mental health issues, but NLP is not regulated or approved by the government.

“None of them are cured as far as I’ve seen, after three days treatment,” Dr. Neil Kitchiner, head of the National Health Service (NHS) All Wales Veterans Health and Wellbeing service, told the BBC. “Some have been made very unwell as a result of going there and have needed a lot of support from NHS and veterans’ charities. We have asked them to stop it.”

Healing the Wounds, the charity set up by Kevin and Carol Richards, has raised a large sum of money in the past three years and claims the NLP treatment is a safe alternative therapy for veterans. According to the BBC, the charity is gathering data to prove the efficacy of its treatment. But the couple running the charity does not check a person’s medical and mental health history before they begin to treat them, and this can lead to “dangerous” problems, according to Professor Neil Greenberg, co-director of the Academic Centre for Defence Mental Health at Kings College London.

An anonymous veteran who attended a three-day therapy session at a hotel, said the therapy made him feel suicidal: “I did two full days and on the third I left and my wife came to collect me,” he told the BBC. “When she came through the doors it was such a relief, I was left feeling worse than when I first went into Healing The Wounds.”

Neuro-linguistic programming is a method developed in the 1970s by Richard Bandler and John Grinder, both of whom were self-help authors and speakers with no medical or scientific background. NLP claims a connection between neurological processes, linguistics, and behavioral patterns, and that these can be changed or adjusted to achieve goals. Practitioners often claim it can treat people within a one-day session. However, not much scientific evidence exists in its favor, and the approach has largely been categorized as a pseudoscience, some even calling it quasi-religious.

The founders of NLP claimed it could treat psychosomatic illnesses, myopia, phobias, depression and even common colds. Matthew B. James, President of The Empowerment Partnership, writes on the Huffington Post that learning NLP can teach people with mental health issues such as anxiety and depression to “switch within seconds to a state in which we can think clearly and creatively, express ourselves authentically, and do whatever we need to do to feel energetic, powerful and happy.”

But with no scientific evidence to back up these claims, and no medical experts who can say it works, UK officials believe NLP should be regulated before being used on individuals with post-traumatic stress disorder or other serious mental health issues. “Because there is no regulation anybody can set up as an NLP practitioner and the quality of their work is not monitored by anybody so that puts potential risks out in the field for anybody accessing those sorts of services,” Darren Millar, chair of the Welsh assembly’s cross-party group on the Armed Forces, told the BBC.