“In the past if I have ever done a photo shoot with so much as a t-shirt on, I have starved myself for weeks in advance and then picked and prodded at every picture and then normally taken the picture down,” he told his 11.4m followers.
The singer then explained how he has decided to “reclaim” his body, adding: “Yesterday I decided to fight the f*** back. Reclaim my body and stop trying to change this chest and these hips and these curves that my mum and dad made and love so unconditionally.
“Some may take this as narcissistic and showing off but if you knew how much courage it took to do this and the body trauma I have experienced as a kid you wouldn’t think those things.”
The 26-year-old went on to thank Ryan Pfluger, the LA/NYC based queer artist and photographer who captured the sunset beach photo for Smith.
“Thank you for helping me celebrate my body AS IT IS @ryanpfluger,” he wrote.
“I have never felt safer than I did with you. I’ll always be at war with this bloody mirror but this shoot and this day was a step in the right f***ing direction.”
Fans praised the star for being so candid about his experiences and for taking steps to embrace his body.
“Your self-acceptance is encouraging inspirational and helpful,” one person commented.
Another added: “Sam, thank you for so beautifully and with brave vulnerability speaking your truth.
“In doing so you give voice and inspiration to those of us listening and watching with similar truths! Nothing but love and respect for you!"
The photographer whom Smith mentioned in the post also shared the same image on his own account where he praised the singer.
“I feel so lucky to have met the people I have in my career & even luckier to create meaningful connections after working with people,” Pfluger wrote.
"@Samsmith thank you for trusting me to facilitate photographs that empower your ownership of your body and mind. I honestly wish everyone relinquished themselves to the experience like you did.
“An experience that has brought us closer together & I look forward to creating with you through the years. All the love. Xoxo”
This isn’t the first time Smith has addressed his body image struggles.
Last year, the “Promises” singer told V magazine: “My body image is always going to be an issue.
”I need to constantly train myself to watch the right sort of films, to not look at certain ads and think that's how my stomach should look.
“It's something that I'm fighting every day. I think men should talk about it more.”
In 2015, he also admitted he deliberately tried to lose weight so that his music would get heard.
“I tried to lose weight and I was making awful music,” he told the BBC.
“It was when I started to be myself that the music flowed.”
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