Dr James O'Donovan, a doctor and YouTuber who also serves as a WHO (World Health Organisation) and Research Director for a global health non-profit, has warned that an unusual sign on your nails could indicate heart disease. In a video discussing the 12 signs of heart disease visible in your skin and nails, he told his followers to look out for splinter haemorrhages.
Unless caused by an injury, these could be a sign of a cardiovascular condition. He described them as "red or purple lines under your nails, which are called splinter haemorrhages, and they're named like this because they look like little splinters of blood".
On white skin, they can appear as red or purple streaks, while on black skin they might look brown or black. Dr O'Donovan added: "Now, most commonly they can be caused by injuries, but if you don't remember hurting your nail then it could be a potential sign of heart disease or other conditions, so it's worth seeing your doctor if this is the case."
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However, he stressed that his channel "is intended as a free open-access educational resource and not as clinical advice", to avoid causing undue anxiety.
Dr James O'Donovan issued the warning (stock)
If you notice any unusual signs or symptoms on your fingers, it's advised to seek advice from the NHS or another healthcare professional. Dr O'Donovan isn't the only expert highlighting potential heart disease symptoms during winter, reports Surrey Live.
Others have also suggested ways to safeguard the respiratory system in colder weather. One such method is altering how we breathe or wearing a mask to lessen the effects of inhaling cold air, according to Asthma and Lung UK's clinical lead, Dr Andrew Whittamore.
He told the Daily Express: "When outside, breathing in through your nose helps to warm up the air, as does wearing a mask or loosely wrapping a scarf around your nose and mouth if it is comfortable to do so. Wearing thermals and layers of thinner clothing instead of one thick layer can keep you warmer too."
Your hands could hint at a cardiovascular condition (stock)
Dr Whittamore also suggested pre-warming your respiratory system with a hot drink before venturing outdoors: "It is also a good idea to have regular hot drinks and check the weather before you go out. Stay inside if it's too cold or windy for you."
He added: "Whatever your winter triggers may be, the most important thing you can do is to use your preventer inhaler regular as prescribed and carry your reliever inhaler with you wherever you go, and make an urgent appointment to see your GP, specialist, or asthma nurse if your symptoms are getting worse."