Dark circles, brittle hair, puffy face and washed-out skin, may not just be high levels or cortisol, but can also point at "Ferritin Face", due to low-ferritin levels. From one content creator asking "Do you have ferritin face?" on TikTok, putting before-and-after style photographs alongside, this is one of the many videos and posts on TikTok and Instagram claiming that low ferritin, a protein which stores iron in the body, can leave visible clues on your face.
The content creators are listing pale or grey-looking skin, dark under-eye circles, dry or cracked lips, hair shedding and weak nails, while others share portraits claiming stark visual differences.
The phrase "ferritin face" has spread widely across social media, with videos attracting millions of views.
But doctors are of the opinion that appearances alone cannot diagnose iron deficiency, and ferritin face isn't a medical diagnosis. Dr Aziza Sesay, general physician at West Midlands, however notes that these changes may be a clue to tell the doctors that something is going on. Pale skin, hair shedding or brittle nails can accompany low iron, but can also be signs of other conditions, she told BBC News.
Ferritin measures your body’s iron reserves, while hemoglobin is the protein in red blood cells that carries oxygen. When haemoglobin drops too low, your blood can't transport enough oxygen throughout your body, leading to a condition known as anaemia.
But iron stores can become depleted before that happens, meaning someone can be iron-deficient and have symptoms without being anaemic. According to the UK guidelines from the British Society of Gastroenterology say ferritin below 15 micrograms per litre indicates absent iron stores, while below 30 generally indicates low iron stores.
"You've got no stored iron but you're maintaining your haemoglobin. That's the big disconnect," said consultant haematologist Dr Drew Provan.
Videos about "ferritin face" often encourage viewers to look for a combination of physical signs - from dark circles and pale skin to dry lips, thinning hair and brittle nails - and compare them with their own appearance.
"You're not ugly, your ferritin is low", one creator says, pointing to the camera.
Dr Provan told BBC that it was "impossible" to determine someone's ferritin levels from how their face looks.
People who are significantly anaemic may look pale, he explained, while fatigue can contribute to dark circles, but these visual signs are "subjective and unreliable".
In people with darker skin, changes in skin colour may be less obvious, Dr Sesay added, meaning someone looking specifically for the signs described online could miss iron deficiency.
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