The Australian Medical Association has backed equal marriage, arguing that homophobic discrimination impacts negatively on gay Australians.

The body added its voice to the growing number of industry leaders who have declared their support for equality.

The country’s right-wing Prime Minister Malcolm Turnbull continues to refuse to allow a free vote in Parliament on the issue, despite overwhelming public support.

In a statement the body – which represents thousands of doctors, medical practitioners and medical students across Australia – alleged that banning same-sex couples from getting married can be “damaging” to their long-term wellbeing.

In a letter to Mr Turnbull and pro-equality opposition leader Bill Shorten, AMA President Dr Michael Gannon urged a united approach to bringing about equality.

He wrote: “Discrimination has a severe, damaging impact on mental and physiological health outcomes, and LGBTIQ individuals have endured a long history of institutional discrimination in this country.

““Many of these inequalities have been rightly nullified… [but] LGBTIQ-identifying Australians will not enjoy equal treatment under Australian law until they can marry.

“It is the AMA’s position that it is the right of any adult and their consenting adult partner to have their relationship recognised under the Marriage Act 1961, regardless of gender.

“There are ongoing, damaging effects of having a prolonged, divisive, public debate, and the AMA urges the Australian Parliament to legislate for marriage equality to resolve this.

The statement cites data showing that people who identify as LGBTIQ have significantly poorer mental and physiological health outcomes than those experienced by the broader population.

The AMA adds that LGBT people are also “more likely to engage in high-risk behaviours such as illicit drug use or alcohol abuse, and have the highest rates of suicidality of any population group in Australia.”

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Dr Gannon continued: “These health outcomes are a consequence of discrimination and stigmatisation, and are compounded by reduced access to health care, again due to discrimination.

“The lack of legal recognition can have tragic consequences in medical emergencies, as a person may not have the right to advocate for their ill or injured partner, and decision-making may be deferred to a member of the patient’s biological family instead.

“Marriage equality has been the subject of divisive political and public debate for the best part of the past decade.

“It is often forgotten that, at the core of this debate, are real people and families. It’s time to put an end to this protracted, damaging debate so that they can get on with their lives.

“As long as the discrimination against LGBTIQ people continues, they will continue to experience poorer health outcomes as a result.

“LGBTIQ Australians are our doctors, nurses, police officers, teachers, mothers, fathers, brothers, and sisters. They contribute to this country as much as any Australian, but do not enjoy the same rights.

“It is time to remove this discrimination.”

The statement has been welcomed by proponents of LGBT equality.

Co-Chair of Australian Marriage Equality Alex Greenwich said: “The AMA’s support for marriage equality highlights the important health and well being benefits of treating all citizens equally and fairly.

“Doctors know from first hand experience the tragic consequences in medical emergencies that come from the lack of equal legal recognition of same-sex partners.

“We hope their support sends a strong message to our parliamentarians that delivering his reform can only be good for Australia, and continued delay is cruel and unnecessary.

“It is great that the AMA has joined other leading national health organisations including Beyond Blue, Headspace and the Australian Media Students Association in supporting this straightforward reform.”

Co-Chair of Australians for Equality (A4E) Anna Brown added: “Unfortunately it’s all too common for service providers such as hospitals to ignore or misunderstand the law and deny same-sex partners recognition as next of kin or beneficiaries.

“It is often at the worst of times that same-sex couples face problems being recognised as next of kin. In times of tragedy when families are dealing with sudden illness or injury, same-sex partners shouldn’t face the indignity or embarrassment of ‘proving’ their relationship to officials.

“Marriage equality will ensure same-sex couples have the comfort and security of knowing their relationship is recognised in the eyes of the law, and removes any need to satisfy the evidentiary requirements of a de facto relationship.

“Same-sex or gender diverse couples in de facto relationships, married overseas or registered with state based schemes face varying degrees of recognition and protection depending on what where they live or travel to.

“Reforming the Marriage Act would ensure the certainty of legal recognition would be available to all couples on an equal basis everywhere across the country.

“LGBTI Australians should have the same opportunities for love, commitment and happiness as everyone else.

“We cannot stress enough that this reform is simply about extending the right of civil marriage to all Australians.”

Just.equal spokesperson, Ivan Hinton-Teoh, said: “I congratulate the AMA on its support for marriage equality.

“The AMA has highlighted what we have known for many years – legal inequality leads directly to poorer health outcomes for LGBTI people.”

“If this Government cares about the health and wellbeing of LGBTI Australians and their families it will allow a free vote so marriage equality can pass straight away.”

Long time marriage equality advocate, Rodney Croome, added: “The AMA’s concern about the health of LGBTI Australians is a reminder that we should never go down the path of a plebiscite.”

“The poorer health outcomes caused by existing legal discrimination would be exacerbated by the discriminatory and stigmatising statements we would see during a plebiscite.”