Lovato, who rose to fame as a teenage movie star and has become one of the world's most popular singers over the past decade, made the announcement to fans in a video and tweets posted online on Wednesday.
"I feel that this best represents the fluidity I feel in my gender expression, and allows me to feel most authentic and true to the person I both know I am and still am discovering," the singer said.
Lovato added they came to the decision "after a lot of healing and self-reflective work."
"I'm still learning & coming into myself, & I don't claim to be an expert or a spokesperson. Sharing this with you now opens another level of vulnerability for me," Lovato said.
"I'm doing this for those out there that haven't been able to share who they truly are with their loved ones. Please keep living in your truths & know I am sending so much love your way."
The "Sorry Not Sorry" hitmaker recently shared their personal struggles with mental health and addiction in a YouTube documentary, which followed their journey prior to and following a near-fatal overdose in 2018.
"My doctors said that I had five to 10 more minutes," Lovato says in the documentary, speaking about the incident.
In a subsequent interview with EW, Lovato said ending their engagement to actor Max Ehrich helped them understand they are "just too queer" for such a commitment to a man at the moment.
"Regardless if drama is happening or not, I am too gay to marry a man right now," Lovato said. "I don't know if that will change in 10 years and I don't know if that'll never change, but I love accepting myself."
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