Lena Durham has been on the receiving end of a significant amount of criticism since her hit show, Girls, went on the air and this time she has attracted headlines because of her recent weight loss.

Lena DunhamLena Dunham has spoken out about her recent weight loss

The creator, writer and star of the HBO show has been in the news for her dramatic new look but took to Instagram to hit back at critics who have commented on her new figure.

In a powerful message to fans, the American actress said her change in weight "isn’t some sign I’ve finally given in to the voices of trolls".

Explaining the reasons for her change in shape, the 30-year-old said: "Right now I’m struggling to control my endometriosis through a healthy diet and exercise.

"So my weight loss isn’t a triumph.

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"I feel I’ve made it pretty clear over the years that I don’t [care] what anyone else feels about my body."

Writing on the social media site, Durham continued: "I’ve gone on red carpets in couture as a size 14. I’ve done sex scenes days after surgery, mottled with scars.

"I’ve accepted that my body is an ever-changing organism, not a fixed entity - what goes up must come down and vice versa."

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She added: "I smile just as wide no matter my current size because I’m proud of what this body has seen and done and represented."

The star is well-known for speaking out about her weight and has previously criticised a magazine who she thought had photoshopped her to make her look thinner - although it hadn’t.

Earlier this year, she praised Glamour magazine for not airbrushing her figure.

Dunham also criticised news outlets that posted before and after pictures of her shape asking: "Don’t we have infinitely more pressing news to attend to?"