Gigi Hadid has revealed that she suffers with a type of thyroid disease.
She told Elle Magazine: "My metabolism actually changed like crazy this year.
"I have Hashimoto's disease.
"It's a thyroid disease, and it's now been two years since taking the medication for it, so for the Victoria Secret show I didn't want to lose any more weight, I just want to have muscles in the right place, and if my butt can get a little perkier, then that's good."
In the same interview, she says when people are cruel about her body she screams into a pillow to release some tension - a trick she says she picked up from her mum.
"Literally, screaming into a pillow helps," she said.
"One time I was on set for a beach shoot, and my mum said, 'Go scream into the ocean. It relieves the tension.'"
What is Hashimoto's disease?
The thyroid gland is found in the neck and it controls the body's growth and metabolism.
If you have Hashimoto's disease, your immune system mistakenly attacks your thyroid gland, causing it to gradually swell and become damaged.
According to the NHS, people who suffer with it will have symptoms of an underactive thyroid gland, which can include fatigue, weight gain, constipation, dry skin and depression.
In some cases the swollen thyroid gland may also cause a lump to form in your throat, known as a goitre.
It's not known what causes Hashimoto's disease but it sometimes appears to run in families.
Hashimoto's thyroiditis can't be cured, but the symptoms are often easily treated with a thyroid hormone replacement medication, which is usually taken for life.
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