Latest news with #diseases
BBC News
15 hours ago
- Health
- BBC News
Why your fingers wrinkle in water (and what it can reveal about your health)
The skin on our fingertips and toes shrivels like prunes when soaked for a few minutes in water. But is this an adaptation that occurred to help us in our evolutionary past? And what can it reveal about your health today? Spend more than a few minutes soaking in a bath or paddling around a swimming pool and your fingers will undergo a dramatic transformation. Where there were once delicate whorls of lightly ridged epidermis, engorged folds of ugly pruned skin will now be found. And according to a recently published study, this striking change is worth a closer inspection – each time your fingertips pucker in this way, the wrinkles create the same pattern. It is the latest discovery about a phenomenon that has occupied the thoughts and work of scientists for decades. Bafflingly, only the skin on our fingers and toes wrinkles when immersed in water. Other body parts such as our forearms, torso, legs and face remain no more crinkled than they were before being submerged. Most researchers in the field have puzzled over what causes this puckering in the first place, but more recently the question of why and what purpose it may serve, has attracted their attention. Perhaps more intriguing still, however, is what our shrivelled fingers can reveal about our own health. Scientists have discovered changes in how our fingers wrinkle can point to diseases including type 2 diabetes, cystic fibrosis, nerve injuries and even cardiovascular problems. What causes our fingers to wrinkle It takes around 3.5 minutes in warm water – 40C (104F) is considered the optimal temperature – for your fingertips to begin wrinkling, while in cooler temperatures of about 20C (68F) it can take up to 10 minutes. Most studies have found it takes around 30 minutes of soaking time to reach maximum wrinklage, however. (Interestingly, recent research has shown that soaking your hands in warm vinegar can make your skin wrinkle far faster – in around just four minutes.) Fingertip wrinkling was commonly thought to be a passive response where the upper layers of the skin swelled as water flooded into the cells via a process known as osmosis – where water molecules move across a membrane to equalise the concentration of the solutions on either side. But as long ago as 1935, scientists have suspected there is more to the process than this. Doctors studying patients with injuries that had severed the median nerve – one of the main nerves that run down the arm to the hand – found that their fingers did not wrinkle. Among its many roles, the median nerve helps to control so-called sympathetic activities such as sweating and the constriction of blood vessels. Their discovery suggested that the water-induced wrinkling of fingertips was in fact controlled by the nervous system. Later studies by doctors in the 1970s provided further evidence of this, and they proposed using the immersion of the hands in water as a simple bedside test to assess nerve damage that might affect the regulation of unconscious processes such as blood flow. Then in 2003, neurologists Einar Wilder-Smith and Adeline Chow, who were working at the National University Hospital in Singapore at the time, took measurements of blood circulation in the hands of volunteers as they soaked them in water. They found that as the skin on the volunteers' fingertips began to wrinkle, there was a significant drop in blood flow in the fingers. When they applied a local anesthetic cream that caused the blood vessels in the fingers of healthy volunteers to temporarily constrict, they found it produced similar levels of wrinkling as water immersion. "It makes sense when you look at your fingers when they go wrinkly," says Nick Davis, a neuroscientist and psychologist at Manchester Metropolitan University, who has studied fingertip wrinkling. "The finger pads go pale and that is because the blood supply is being constricted away from the surface." Wilder-Smith and his colleagues proposed that when our hands are immersed in water, the sweat ducts in our fingers open up to allow water in, which leads to an imbalance in the salts in our skin. This change in the salt balance triggers the firing of nerve fibres in the fingers, leading to the blood vessels around the sweat ducts to constrict. This in turn causes a loss of volume in the fleshy area of the fingertip, which pulls the overlying skin downwards so that it distorts into wrinkles. The pattern of the wrinkles depends on the way the outermost layer of skin – the epidermis – is anchored to the layers beneath it. More like this: There have also been suggestions that the outer layers of skin may also swell a little to enhance the wrinkling. By osmosis alone, however, our skin would need to swell by 20% to achieve the wrinkles we see in our fingers, which would leave them hideously enlarged. But when the upper layers of skin swell slightly and the lower levels shrink at the same time, the wrinkling becomes pronounced far sooner, says Pablo Saez Viñas, a biomechanical engineer at the Technical University of Catalonia, who has used computer modelling to examine the mechanism. "You need both to have normal levels of wrinkles," he says. "If you don't have that neurological response, which happens in some individuals, wrinkles are inhibited." But if wrinkling is controlled by our nerves, it means our bodies are actively reacting to being in water. "That means it is happening for a reason," says Davis. "And that means it could be giving us an advantage." Why did our fingers evolve to wrinkle in water? It was a question from one of his children during a bath about why their fingers had gone wrinkly that recently led Davis to dig into what this advantage could be. With the help of 500 volunteers who visited the Science Museum in London during 2020, Davis measured how much force they needed to use to grip a plastic object. Perhaps unsurprisingly, those with dry, unwrinkled hands needed to use less force than people whose hands were wet – so their grip on the object was better. But when they submerged their hands in a water bath for a few minutes to turn their hands wrinkly, the grip force fell between the two even though their hands were still wet. "The results were amazingly clear," says Davis. "The wrinkling increased the amount of friction between the fingers and the object. What is particularly interesting is that our fingers are sensitive to this change in the surface friction and we use this information to apply less force to grip an object securely." The object that Davis' volunteers were gripping weighed less than a couple of coins, so the amount of grip required was small. But when performing more arduous tasks in a wet environment, this difference in friction could become more important. "If you don't have to squeeze as hard to grip something, the muscles in your hands get less tired and so you can do it for longer," he says. His findings match those by other researchers who have found that the wrinkling of our fingertips makes it easier for us to handle wet objects. In 2013, a team of neuroscientists at Newcastle University in the UK asked volunteers to transfer glass marbles of varying sizes and fishing weights from one container to another. In one case the objects were dry, and in the other they were at the bottom of a container filled with water. It took 17% longer for the participants to transfer the submerged objects with unwrinkled fingers than when they were dry. But when their fingers were wrinkled, they could transfer the submerged marbles and weights 12% quicker than when their fingers were wet and unwrinkled. Interestingly, there was no difference in transferring the dry objects with wrinkled or unwrinkled fingers. There are other baffling mysteries – women take longer to develop wrinkles than men do Some scientists have suggested that the wrinkles on our fingertips and toes may act like rain treads on tyres or the soles of shoes. The channels produced by the wrinkles help to squeeze water away from the point of contact between the fingers and an object. This suggests that humans may have evolved fingertip and toe wrinkling at some point in our past to help us grip wet objects and surfaces. "Since it seems to give better grip under water, I would assume that it has to do with either locomotion in very wet conditions or potentially with manipulating objects under water," says Tom Smulders, an evolutionary neuroscientist at Newcastle University who led the 2013 study. It could have given our ancestors a key advantage when it came to walking over wet rocks or gripping branches, for example. Alternatively, it could have helped us when catching or foraging for food such as shellfish. "The latter would imply it is unique to humans, whereas if it's the former, we would expect it to happen in other primates as well," says Smulders. Finger wrinkling has yet to be observed in our closest relatives in the primate world such as chimpanzees, but the fingers of Japanese macaque monkeys, which are known to bath for long periods in hot water, have been seen to also wrinkle after they have been submerged in water. But the lack of evidence in other primates does not mean it doesn't happen, it may simply be because no-one has looked closely enough yet, says Smulders. "We don't know the answer to this question yet." There are some other interesting clues about when this adaptation may have appeared in our species. Fingertip wrinkling is less pronounced in saltwater and takes longer than it does in freshwater. This is probably because the salt gradient between the skin and surrounding environment is lower in saltwater, and so the salt imbalance that triggers the nerve fibres is less dramatic. So, it could be an adaptation that helped our ancestors live in freshwater environments rather than along coastlines. But there are no firm answers, and some believe it could just be a coincidental physiological response with no adaptive function. What can we learn from the wrinkles? Strangely there are other baffling mysteries – women take longer to develop wrinkles than men do, for example. And why exactly does our skin return to its normal state – normally after 10-20 minutes – if there is no clear disadvantage to our grip on dry objects of having wrinkly fingertips? Surely if having wrinkly fingers can improve our grip in the wet, but not harm it when dry, why would our fingertips not be permanently wrinkly? One reason for that could be the change in sensation the wrinkling also causes. Our fingertips are packed with nerves, and the pruning of our skin changes the way we feel things we touch (although one study has shown it does not affect our ability to discriminate between objects based on touch). "Some people have a real aversion to it because picking something up with wrinkly fingers feels weird," says Davis. "It could be because the balance of skin receptors have changed position, but there could be a psychological dimension too. It would be fun to investigate why. There could be other things we can do less well with wrinkly fingers." But the wrinkling of our fingers and toes in water can reveal key information about our health in surprising ways too. Wrinkles take longer to form in people with skin conditions like psoriasis and vitiligo, for example. Patients with cystic fibrosis experience excessive wrinkling of their palms as well as their fingers, and this has even been noticed in people who are genetic carriers of the disease. Patients suffering from type 2 diabetes also sometimes show markedly decreased levels of skin wrinkling when their hands are placed in water. Similarly reduced wrinkling has been seen in people who have suffered heart failure, perhaps due to some disruption in the control of their cardiovascular system. Unsymmetrical wrinkling of the fingers – where one hand wrinkles less than the other despite the same immersion time – has even been suggested as an early sign of Parkinson's disease as it indicates the sympathetic nervous system is not functioning correctly on one side of the body. So, while the question of why our fingers and toes began wrinkling in water in the first place remains open, our pruney digits are proving useful to doctors in other surprising ways. * This article was originally published on 21 June 2022. It was updated on 19 June 2025 to include details of a new study on the repeatability of wrinkle patterns on wet fingers. -- If you liked this story, sign up for The Essential List newsletter – a handpicked selection of features, videos and can't-miss news, delivered to your inbox twice a week. For more science, technology, environment and health stories from the BBC, follow us on Facebook, X and Instagram.
Daily Mail
2 days ago
- Health
- Daily Mail
EXCLUSIVE Doctors can notice cancer and diabetes in your eyes... are you overlooking the clues?
The eyes are the window to the soul, but they may also be the key to spotting deadly diseases, doctors warn. Dark specks on the iris could just be a sign of too much summertime sunshine. But in rare cases, they could be the first clue to spotting deadly eye cancers. Your browser does not support iframes.
Zawya
13-06-2025
- Health
- Zawya
Tunisia to host 1st MENA Region "One Health" Conference June 14-15
Tunis – Tunisia is hosting the first MENA Region 'One Health' Conference on June 14 and 15, with the participation of 17 regional countries and 40 high-level officials, including 10 ministers representing health, agriculture, and environment sectors, as well as directors-general, ministry representatives, and UN officials, announced Hechmi Louzir, president of the conference's scientific committee. The conference will also bring together representatives from international organisations such as the World Bank (the event's funder), the World Health Organisation (WHO), the Food and Agriculture Organisation (FAO), the UN Environment Programme (UNEP), and the World Organisation for Animal Health (OIE). During a press conference held Thursday at the Pasteur Institute of Tunis, Louzir emphasised that this event presents a key opportunity to enhance regional and international cooperation in tackling emerging pandemics and diseases through a unified approach linking health, environment, and agriculture sectors. He noted that Tunisia will propose the "Carthage Declaration for One Health," a joint pact between health, agriculture, and environment ministries, which has already been shared with participating countries. The declaration aims to establish core principles of the "One Health" approach through collective stakeholder engagement. "The adoption of this declaration by conference participants is expected," he added. Louzir highlighted that the "One Health" approach has become essential, given that over 70% of human diseases originate from animals. Hosting this conference in Tunisia will help produce concrete recommendations and develop effective strategies to combat pandemics, he said. Abderrazek Bouzouita, Director-General of Health at the Ministry of Health, stressed that the "One Health" approach will unify efforts and policies at national, regional, and international levels, especially as climate change and new diseases threaten ecosystems. He added that the conference aims to strengthen partnerships, **share expertise and produce a joint declaration to implement decisions across sectors. Wahib Mehri, Director-General of Veterinary Services at the Ministry of Agriculture, Fisheries, and Water Resources, emphasised the need for a dedicated structure to ensure coordination between health, agriculture, and environment ministries, enabling real-time data sharing to prevent disease outbreaks. Mosbah Abaza, Director-General of Sustainable Development at the Ministry of Environment, pointed out the interconnectedness of environmental, agricultural, and health systems, warning that disruptions in one sector can severely impact others. The ministry plays a key role in "One Health" through wastewater treatment, waste management, and coastal protection initiatives, he said.
The Guardian
11-06-2025
- Health
- The Guardian
Progress unravelled, and millions left vulnerable: how British aid cuts threaten British health too
Right now, aid reductions across the globe are jeopardising decades of progress against preventable diseases, leaving millions of people vulnerable. This retreat from global health threatens to unravel hard-won advances against diseases we have nearly conquered. Polio, which paralysed hundreds of thousands of children annually just 40 years ago, has been eliminated in most parts of the world. Meanwhile, there has been a resurgence of diseases such as measles and cholera in populations besieged by conflict and climate emergencies. Britain faces a critical choice: follow this global trend of disengagement or stand firm as a bulwark for international health security. I understand the tough trade-offs the government must make to get public spending under control, but the stakes extend beyond humanitarian concerns to our own national interests. Last year, the detection of poliovirus in UK sewers threatened our own children and delivered a reminder that diseases respect no borders. Our protection at home depends directly on our commitment to efforts abroad. Yet the government's budget spending review promises precisely the wrong direction. By slashing international aid to a 25-year low – from 0.5% of gross national income to just 0.3% – to finance increased defence spending, the government paradoxically risks undermining our own domestic health security. In real terms, this would gut our development assistance by 40% in just four years. Such draconian cuts would severely undermine all major global health initiatives. Of course, fiscal prudence is necessary, but how can we ignore the humanitarian and strategic costs of these reductions? Even beyond self-protection, a strong global health budget surely reflects our deepest values. No child should die from a disease we can prevent. Threats to global health inevitably become threats to Britain's health, and all our protection depends on maintaining our international leadership in this field. Now, as vulnerable children face renewed threats from these very diseases, polio stands as a glaring example of what is at stake. In 1988, the Global Polio Eradication Initiative (GPEI) was formed – a landmark public-private partnership led by national governments alongside partners including Rotary International, the World Health Organization and Unicef. This collaborative effort is crucial for tackling a major health threat such as polio. Since worldwide vaccination efforts began, an estimated 20 million children who would have been paralysed are walking today, and approximately 1.6 million deaths have been averted. This is remarkable, but fragile, progress. In 2024, the number of children paralysed rose in Pakistan and Afghanistan, the two remaining endemic countries. In grim examples of how conflict can upend everything, polio paralysed a child in Gaza for the first time in two decades last year and continues to afflict families in Sudan. Not investing in polio could translate to 200,000 new cases of the disease every year, including in countries where it has long been eradicated, and cost the world billions. Pound for pound, prevention has consistently proved to be a 'best buy' compared with endlessly responding to outbreaks. The financial case for continued investment in polio eradication is unassailable. Yet the global eradication agenda faces a critical funding gap of about £1.7bn to meet its overall £5bn target. The UK has invested £1.3bn since 1988 and is one of the effort's staunchest backers. Support is needed now more than ever. At its core, the GPEI is a partnership. To abandon our commitments now, on the threshold of ending polio for good, would undermine decades of investment, leave millions of children unprotected and ultimately cost more in the long run. We have the tools to end polio for good, along with strong public backing: last month, more than 85,000 people across the UK participated in the Rise Together movement challenge in support of efforts to end the disease. As Britain faces its most challenging fiscal scrutiny in decades, the decisions made today will define our country's economic success – as well as our reputation as stewards of a safer, healthier world for all. The budget spending review presents an opportunity to state unequivocally that the UK will maintain a long-term commitment to protecting children worldwide, including our own, from preventable diseases. The choice before us is clear. We can honour a proud tradition of global health leadership by maintaining our commitment to eradicate polio once and for all, or we can retreat at the very moment victory is within reach. Sarah Champion is the Labour MP for Rotherham
Forbes
08-06-2025
- General
- Forbes
Meet 4 ‘Killer' Birds That Have Been Known To Attack People — Explained By A Biologist
Do you know what the world's most deadly animal is? I'll give you a hint. It has wings and is capable of flight – but it's not a bird. The answer? A mosquito. Mosquitoes are a true scourge, responsible for up to one million human deaths per year. Mosquitoes aren't deadly from their bites alone – though, to be fair, a swarm of mosquitos is not something to overlook as they can kill cattle, horses and other large mammals in rare cases. Rather, what makes them so dangerous are the diseases they carry – malaria, dengue, yellow fever and others. Birds, on the other hand, can also be dangerous to humans due to the contagions they carry – the most common being avian flu, or H5N1. Nevertheless, the danger posed by bird flu is orders of magnitude less than that of malaria. To give some context, confirmed human deaths from bird flu over the past two decades is less than 500. I repeat: mosquitoes kill up to a million people per year. The odds of human death or injury by bird attack is even more remote. But it does happen. When it does, it's often inflicted by one of the following four bird species – two of which we have documented evidence of human fatalities. Southern cassowary (Casuarius casuarius). getty Often dubbed 'the world's most dangerous bird,' the cassowary (Casuarius spp.) lives in the rainforests of northern Australia and New Guinea. These flightless birds are striking in appearance – bright blue skin, a helmet-like casque on their heads, and dagger-like claws on each foot. While they are usually shy and elusive, cassowaries can become highly aggressive if they feel threatened, especially during breeding season or when defending chicks. Their most fearsome weapon is a sharp, curved claw on each foot, which can grow up to 5 inches long. With a single kick, they can slash open skin and sever arteries. One of the first documented fatal cassowary attacks occurred in Australia in 1926, when a 16-year-old boy reportedly tried to club and kill the bird. The cassowary kicked him in the neck, severing his jugular vein. He died shortly afterward from his injuries. More recently, a 75-year-old man was killed by a cassowary at an exotic animal breeding farm in Florida, where the bird was being kept in captivity. The man suffered more than a dozen lacerations from the bird's sharp claws and died shortly after paramedics arrived on the scene. Many other attacks have been reported in Australia, though most are non-fatal. Australian magpie (Gymnorhina tibicen). getty Australian magpies (Gymnorhina tibicen) are notorious for their aggressive swooping behavior during breeding season, particularly from August to October. Found throughout Australia, these medium-sized birds are highly territorial and will defend their nests with surprising boldness against much larger intruders, including humans. Cyclists, joggers, and walkers are common targets, especially if they inadvertently stray too close to a nesting site. Attacks usually involve fast, low swoops from behind, often accompanied by loud squawking. While many incidents result in no more than a scare, some have caused eye injuries, concussions, or cycling accidents. There have been reports of people crashing their bicycles while trying to avoid swooping magpies, leading to broken bones or worse. In rare cases, efforts to avoid these swooping birds have ended in tragedy. In 2019, a 76-year-old man from Sydney died from head injuries sustained in a bicycle accident while trying to evade a swooping magpie. Experts suggest that not all magpies are aggressive. Only about 10% of male magpies engage in this behavior, and they often remember individual humans they perceive as threats. Wearing sunglasses on the back of your head, using zip-ties on helmets, or avoiding known nesting areas during breeding season are all common countermeasures. (Sidebar: While the birds discussed here attack humans only in self-defense or to defend territory, meet two birds of prey that may have viewed humans as a source of food: one is recently extinct and the other lives on in this region of the Americas.) Ostrich (Struthio camelus). getty The ostrich (Struthio camelus), the world's largest bird, may not be able to fly but its long legs and stature make it a serious threat if provoked. Native to Africa, ostriches can stand over 9 feet tall and weigh upwards of 300 pounds. Their long legs are incredibly powerful, capable of delivering a deadly kick with sharp, clawed toes. These kicks are strong enough to kill large predators like lions, and can easily injure or kill a human. Ostriches are generally peaceful grazers, but during breeding season or when cornered, they can become extremely defensive. Males, in particular, are known to be aggressive when guarding a mate or nest. Attacks on humans typically occur in captivity or farming situations, where humans may unknowingly enter their territory. Emu (Dromaius novaehollandiae). getty The emu (Dromaius novaehollandiae) is Australia's second-largest bird after the cassowary and, while less aggressive, it can still pose a threat under certain conditions. Emus are curious, fast-moving, flightless birds that can reach speeds of up to 30 miles per hour and stand over 6 feet tall. Unlike cassowaries, they lack a killing claw, but their powerful legs can inflict serious damage with a kick or shove. Emus are not naturally aggressive toward humans, but like any large wild animal, they can become defensive if startled, provoked, or protecting their territory. Incidents involving emus typically occur in captivity or areas where humans have fed them and altered their natural behavior. In some tourist regions, emus have been known to chase people for food or become overly familiar – leading to head-butts, pecking or the occasional knockdown. During Australia's infamous 'Emu War' in 1932, soldiers struggled to control large flocks of emus that were damaging crops – highlighting both the bird's resilience and wariness. While the emu's reputation is more comedic than fearsome, it's important not to underestimate these towering birds. Giving them space and not feeding wild animals are all key to peaceful coexistence. Are you an animal lover who owns a pet, perhaps even a (friendly) pet bird? Take the science-backed Pet Personality Test to know how well you know your animal.
