Zoe Saldana has been a constant on our screens since the early 2000s, always appearing to be the picture of good health, so it comes as a surprise that the star has the autoimmune condition Hashimoto's thyroiditis.
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The condition is caused by the immune system attacking the thyroid gland, damaging it and making it swell, destroying it over time, leaving it unable to produce enough thyroid hormone.
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Symptoms include fatigue and muscle pain, along with dry skin and weight gain – and Zoe isn't the only member of her family who has it.
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The From Scratch actress told Net-A-Porter's The Edit in 2016 that although her mother and grandmother suffer from the condition, she believed herself to be immune.
"I had a great time in my twenties," she said. "Then your doctor says you're losing calcium in your bones.
Zoe Saldana didn't notice symptoms of Hashimoto's until she was in her thirties
"I would hear those conversations with my mom and grandma, thinking I'd never get there. I'm going to live forever! But all of a sudden it hits you."
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Zoe is fortunate that she was able to recognize the symptoms, which normally set in between the ages of 30 and 50, because Hashimoto's can take months or even years to be detected because it progresses very slowly.
Hashimoto's is hard to detect
Explaining the realities of her condition, Zoe said: "Your body doesn't have the energy it needs to filter toxins, causing it to believe that it has an infection, so it's always inflamed. You create antibodies that attack your glands, so you have to eat clean."
Zoe said her lifestyle is the main way she manages the condition, following a gluten-free and dairy-free diet.
While Hashimoto's cannot be cured, the symptoms can be treated with a medicine that replaces the missing hormone.
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