Professor David Galloway, former President of the Royal College of Physicians and Surgeons of Glasgow, and Dr Peter Saunders, CEO of the International Christian Medical and Dental Association, are among the experts to appear on a new DVD for schools challenging transgenderism.

The "Truth in Science" video is being sent to every school in the country and every MP in Parliament to raise awareness about the dangers of transgender ideology.

Contrary to the claims of trans activists, the DVD argues that biological sex is not something that can be changed, and is rather determined at conception.

The experts also assert that gender dysphoria is based in the mind and should be treated as any other mental illness, with "patience and compassion" for the individual.

Professor Andy McIntosh, Director of Truth in Science, an organisation bringing together professionals in the fields of science and education, said he wanted head teachers, school governors and parliamentarians to be informed about the issues and take action to protect children from harmful ideologies and medical intervention. 

"Our hormones system is shown to have a role of maintaining male as male, and female as female. Our genes, our hormones, our biochemistry and physiology, all signify maleness and femaleness," he said.

"Transgenderism suggests we can be a woman trapped in a male body or vice versa, but this is not supported by evidence-based science."

He said that medical treatment could only "fake a change of biological sex" and that it was "wrong and harmful". 

"Doctors, surgeons, paediatricians and professional scientists, all state that we should be offering some form of cognitive therapy, rather than radical surgery that does not solve the issue, but in fact can lead to deep regret and a high rate of suicide," he said. 

He added: "Children are not to be experimented upon, but to be protected and nurtured. As adults we all have a responsibility to see that children entrusted to our care, develop into healthy and well-rounded adults with an opportunity of a full and healthy life."

Join the producers and experts for a live discussion about the DVD and the issues it raises on YouTube on Wednesday 11 November.