Actress Jenny Mollen says her weight loss is likely due to a thyroid problem

Actress Jenny Mollen has responded to concern from fans over her declining weight by revealing she is potentially suffering from a thyroid condition.
 
The Angel star, 38, shared a nude photo on Instagram on Thursday, explaining that she is undergoing tests to determine the cause of her thin frame.
 
“Not anorexia, it’s a thyroid issue,” Mollen, who is married to fellow actor Jason Biggs, wrote.

“I don’t know what it says about me that I got this thin and didn’t think there was anything wrong.”

Mollen's weight had been dropping rapidly in the six months since she welcomed her second child, prompting fans to contact her and ask about it.
 
However, she didn’t seek medical advice until last week, when she noticed a bulge “the size of a golf ball” in her neck.

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The mum of two is still waiting on the results of her blood test and ultrasound, but she said her doctor believed the diagnosis will be Graves' disease.

The autoimmune disorder is the most common cause of hyperthyroidism, or an ‘overactive thyroid’ - in other words, the over-production of thyroid hormone.
 
This can increase the metabolism, often resulting in unexpected weight loss along with other symptoms like anxiety, fatigue and breathlessness.

In another Instagram post last week, Mollen said hyperthyroidism was apparently common among women after pregnancy.

On Thursday, she detailed some of the symptoms she’d experienced in the lead-up to undergoing tests.
 
“If you just had a baby and have lost an inordinate amount of weight, feel like you are on cocaine, are suddenly heat intolerant, can’t stop losing hair, and think your husband is being a dick it might just be your thyroid!” she wrote.

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Several fans - many of them fellow mums - shared their own experience with Graves' disease and other thyroid conditions in the comments.
 
“I was diagnosed with Graves/hyper last summer almost two years after having my third child,” one wrote. 

“I now think back to everything I chalked up to just being part of ‘postpartum’ - probably wasn’t.”