A forthcoming study finds transgender and cisgender veterans are similar in regard to mental and physical health.

The Department of Defense announced today a policy to prevent transgender people from serving in the U.S. military, citing risks to military effectiveness and lethality and unit cohesion.

According to research from the Williams Institute, an estimated 15,500 transgender adults are serving in the US military, including 8,800 on active duty and 6,700 in the National Guard or Reserves. In addition, there are approximately 134,300 transgender veterans.

A forthcoming Williams Institute study using data from the Centers for Disease Control and Prevention found few health differences between transgender and cisgender veterans. Researchers compared 13 indicators of mental and physical health, such as substance use, exercise, access to health care and depression, for both transgender and cisgender veterans.

Preliminary data shows that transgender veterans differed only in their likelihood to have at least one disability and to have experienced mental distress in the past 30 days. However, transgender veterans were found to have higher rates of poverty than cisgender veterans, which may – at least in part – contribute to the observed health differences.

"When we look at veterans, transgender and cisgender veterans look pretty similar to each other in regard to health," says Jody L. Herman, a scholar of public policy at the Williams Institute. "This could be due to the fact that protocols that determine who can enter military service have been working equally well over the years for transgender and cisgender individuals."

In terms of unit cohesion, preliminary qualitative data from the Military Acceptance Project, a $1.8 million study funded by the U.S. Department of Defense focused on understanding integration of LGBT people into the military, finds that transgender service members have an intense commitment to their country and the U.S. military. In addition, many have experienced acceptance from their peers and superiors.

"The idea that transgender service members are disruptive is unfounded," says Ian W. Holloway, visiting scholar at the Williams Institute and co-principal investigator of the Military Acceptance Project. "Eighteen countries, including the UK and Germany, allow transgender people to serve openly in the military and none report a negative impact on operational preparedness or unit cohesion."