A doctor has issued a disturbing warning to those who are partial to eating an old spud.
According to Dr Samuel Choudhury, a GP from Singapore, potatoes that have been lurking in the cupboard for a little while could harbour a potentially deadly toxin.
In a clip shared with his 216,000 Instagram followers, Dr Choudhury advised steering clear of potatoes that have sprouted shoots — as well as ones that have turned green.
It is well known that green patches on spuds indicate presence of the toxin solanine, which can cause painful digestive symptoms as well as hallucinations, paralysis, and even death in severe cases.
But Dr Choudhry says the poison can also be bound up in sprouts that form on spuds that are exposed to a light and humid environment for a week or two.
In his social media video, Dr Choudhury told the cautionary tale of Maria Harless, a young woman from Denver, Colorado who had 'a sudden craving for mashed potatoes'.
But after eating them and going to sleep she 'took a turn for the worse' and woke up in the middle of the night vomiting, and suffering a pounding headache.
When she arrived at the emergency department doctors realised that a sprouting potato was the culprit, Dr Choudhury explained.
'She was suffering from solanine poisoning — a neurotoxin from potatoes, but not normal potatoes. These (green and sprouting potatoes) are not.
'When you consume a large amount of these (green or sprouting potatoes) it can cause diarrhoea, vomiting, a headache, irregular heart rhythm and in severe cases death.'
'In one case a family of seven became a family of five, so if you see this I would err on the side of caution and throw them away into compost and just buy new ones,' he added.
Sprouting, the green colour and a bitter taste can be a sign the toxin is present.
Potatoes turn green and start to sprout if they are not kept in the dark, Dr Choudhury explains.
When potatoes are stored in conditions that are too warm, light or moist, their dormant growth nodes, called eyes, start to grow.
Estimates of how much solanine is poisonous varies, but it's thought a toxic dose is thought 1 mg or more of solanine per kilogram of body weight, according to the European Food Safety Authority.
However, if the potato is firm and the sprouts are small, removing them can help eliminate the toxin.
Similarly, peeling the potatoes can also help reduce solanine levels as the compound is most concentrated just beneath the skin.
To keep your spuds fresh, they are best stored in a cupboard that's slightly warmer than the fridge.
