Latest news with #enamel
The Independent
10-06-2025
- Health
- The Independent
Two-million-year-old teeth transform theory of prehistoric human evolution
The enamel that forms the outer layer of our teeth might seem like an unlikely place to find clues about evolution. But it tells us more than you'd think about the relationships between our fossil ancestors and relatives. In our new study, published in the Journal of Human Evolution, we highlight a different aspect of enamel. In fact, we highlight its absence. Specifically, we show that tiny, shallow pits in fossil teeth may not be signs of malnutrition or disease. Instead, they may carry surprising evolutionary significance. You might be wondering why this matters. Well, for people like me who try to figure out how humans evolved and how all our ancestors and relatives were related to each other, teeth are very important. And having a new marker to look out for on fossil teeth could give us a new tool to help fit together our family tree. Uniform, circular and shallow These pits were first identified in the South African species Paranthropus robustus, a close relative of our own genus Homo. They are highly consistent in shape and size: uniform, circular and shallow. Initially, we thought the pits might be unique to P. robustus. But our latest research shows this kind of pitting also occurs in other Paranthropus species in eastern Africa. We even found it in some Australopithecus individuals, a genus that may have given rise to both Homo and Paranthropus. The enamel pits have commonly been assumed to be defects resulting from stresses such as illness or malnutrition during childhood. However, their remarkable consistency across species, time and geography suggests these enamel pits may be something more interesting. The pitting is subtle, regularly spaced, and often clustered in specific regions of the tooth crown. It appears without any other signs of damage or abnormality. Two million years of evolution We looked at fossil teeth from hominins (humans and our closest extinct relatives) from the Omo Valley in Ethiopia, where we can see traces of more than two million years of human evolution, as well as comparisons with sites in southern Africa (Drimolen, Swartkrans and Kromdraai). The Omo collection includes teeth attributed to Paranthropus, Australopithecus and Homo, the three most recent and well-known hominin genera. This allowed us to track the telltale pitting across different branches of our evolutionary tree. What we found was unexpected. The uniform pitting appears regularly in both eastern and southern Africa Paranthropus, and also in the earliest eastern African Australopithecus teeth dating back around 3 million years. But among southern Africa Australopithecus and our own genus, Homo, the uniform pitting was notably absent. A defect … or just a trait? If the uniform pitting were caused by stress or disease, we might expect it to correlate with tooth size and enamel thickness, and to affect both front and back teeth. But it doesn't. What's more, stress-related defects typically form horizontal bands. They usually affect all teeth developing at the time of the stress, but this is not what we see with this pitting. We think this pitting probably has a developmental and genetic origin. It may have emerged as a byproduct of changes in how enamel was formed in these species. It might even have some unknown functional purpose. In any case, we suggest these uniform, circular pits should be viewed as a trait rather than a defect. A modern comparison Further support for the idea of a genetic origin comes from comparisons with a rare condition in humans today called amelogenesis imperfecta, which affects enamel formation. About one in 1,000 people today have amelogenesis imperfecta. By contrast, the uniform pitting we have seen appears in up to half of Paranthropus individuals. Although it likely has a genetic basis, we argue the even pitting is too common to be considered a harmful disorder. What's more, it persisted at similar frequencies for millions of years. A new evolutionary marker If this uniform pitting really does have a genetic origin, we may be able to use it to trace evolutionary relationships. We already use subtle tooth features such as enamel thickness, cusp shape, and wear patterns to help identify species. The uniform pitting may be an additional diagnostic tool. For example, our findings support the idea that Paranthropus is a 'monophyletic group', meaning all its species descend from a (relatively) recent common ancestor, rather than evolving seperatly from different Australopithecus taxa. And we did not find this pitting in the southern Africa species Australopithecus africanus, despite a large sample of more than 500 teeth. However, it does appear in the earliest Omo Australopithecus specimens. So perhaps the pitting could also help pinpoint from where Paranthropus branched off on its own evolutionary path. An intriguing case One especially intriguing case is Homo floresiensis, the so-called 'hobbit' species from Indonesia. Based on published images, their teeth appear to show similar pitting. If confirmed, this could suggest an evolutionary history more closely tied to earlier Australopithecus species than to Homo. However, H. floresiensis also shows potential skeletal and dental pathologies, so more research is needed before drawing such conclusions. More research is also needed to fully understand the processes behind the uniform pitting before it can be used routinely in taxonomic work. But our research shows it is likely a heritable characteristic, one not found in any living primates studied to date, nor in our own genus Homo (rare cases of amelogenesis imperfecta aside). As such, it offers an exciting new tool for exploring evolutionary relationships among fossil hominins.
The Independent
09-06-2025
- Health
- The Independent
Discovery of two-million-year-old teeth reveals secrets of ancient humans
The enamel that forms the outer layer of our teeth might seem like an unlikely place to find clues about evolution. But it tells us more than you'd think about the relationships between our fossil ancestors and relatives. In our new study, published in the Journal of Human Evolution, we highlight a different aspect of enamel. In fact, we highlight its absence. Specifically, we show that tiny, shallow pits in fossil teeth may not be signs of malnutrition or disease. Instead, they may carry surprising evolutionary significance. You might be wondering why this matters. Well, for people like me who try to figure out how humans evolved and how all our ancestors and relatives were related to each other, teeth are very important. And having a new marker to look out for on fossil teeth could give us a new tool to help fit together our family tree. Uniform, circular and shallow These pits were first identified in the South African species Paranthropus robustus, a close relative of our own genus Homo. They are highly consistent in shape and size: uniform, circular and shallow. Initially, we thought the pits might be unique to P. robustus. But our latest research shows this kind of pitting also occurs in other Paranthropus species in eastern Africa. We even found it in some Australopithecus individuals, a genus that may have given rise to both Homo and Paranthropus. The enamel pits have commonly been assumed to be defects resulting from stresses such as illness or malnutrition during childhood. However, their remarkable consistency across species, time and geography suggests these enamel pits may be something more interesting. The pitting is subtle, regularly spaced, and often clustered in specific regions of the tooth crown. It appears without any other signs of damage or abnormality. Two million years of evolution We looked at fossil teeth from hominins (humans and our closest extinct relatives) from the Omo Valley in Ethiopia, where we can see traces of more than two million years of human evolution, as well as comparisons with sites in southern Africa (Drimolen, Swartkrans and Kromdraai). The Omo collection includes teeth attributed to Paranthropus, Australopithecus and Homo, the three most recent and well-known hominin genera. This allowed us to track the telltale pitting across different branches of our evolutionary tree. What we found was unexpected. The uniform pitting appears regularly in both eastern and southern Africa Paranthropus, and also in the earliest eastern African Australopithecus teeth dating back around 3 million years. But among southern Africa Australopithecus and our own genus, Homo, the uniform pitting was notably absent. A defect … or just a trait? If the uniform pitting were caused by stress or disease, we might expect it to correlate with tooth size and enamel thickness, and to affect both front and back teeth. But it doesn't. What's more, stress-related defects typically form horizontal bands. They usually affect all teeth developing at the time of the stress, but this is not what we see with this pitting. We think this pitting probably has a developmental and genetic origin. It may have emerged as a byproduct of changes in how enamel was formed in these species. It might even have some unknown functional purpose. In any case, we suggest these uniform, circular pits should be viewed as a trait rather than a defect. A modern comparison Further support for the idea of a genetic origin comes from comparisons with a rare condition in humans today called amelogenesis imperfecta, which affects enamel formation. About one in 1,000 people today have amelogenesis imperfecta. By contrast, the uniform pitting we have seen appears in up to half of Paranthropus individuals. Although it likely has a genetic basis, we argue the even pitting is too common to be considered a harmful disorder. What's more, it persisted at similar frequencies for millions of years. A new evolutionary marker If this uniform pitting really does have a genetic origin, we may be able to use it to trace evolutionary relationships. We already use subtle tooth features such as enamel thickness, cusp shape, and wear patterns to help identify species. The uniform pitting may be an additional diagnostic tool. For example, our findings support the idea that Paranthropus is a 'monophyletic group', meaning all its species descend from a (relatively) recent common ancestor, rather than evolving seperatly from different Australopithecus taxa. And we did not find this pitting in the southern Africa species Australopithecus africanus, despite a large sample of more than 500 teeth. However, it does appear in the earliest Omo Australopithecus specimens. So perhaps the pitting could also help pinpoint from where Paranthropus branched off on its own evolutionary path. An intriguing case One especially intriguing case is Homo floresiensis, the so-called 'hobbit' species from Indonesia. Based on published images, their teeth appear to show similar pitting. If confirmed, this could suggest an evolutionary history more closely tied to earlier Australopithecus species than to Homo. However, H. floresiensis also shows potential skeletal and dental pathologies, so more research is needed before drawing such conclusions. More research is also needed to fully understand the processes behind the uniform pitting before it can be used routinely in taxonomic work. But our research shows it is likely a heritable characteristic, one not found in any living primates studied to date, nor in our own genus Homo (rare cases of amelogenesis imperfecta aside). As such, it offers an exciting new tool for exploring evolutionary relationships among fossil hominins.
Daily Mail
09-06-2025
- Entertainment
- Daily Mail
How your teeth can make you look much older: Experts reveal the 13 ways to anti-age your smile - plus the £11.50 lipstick that'll instantly whiten teeth
No matter how good your hair cut, how toned your triceps or how well you've nailed smooth Botoxed skin, one thing that gives away your age is an unpolished smile. Coffee and red wine stains, chipped enamel and receding gums make you look long in the tooth, and if you find yourself pulling a rictus grin in selfies to cover up, you may need some help.
Telegraph
22-05-2025
- Health
- Telegraph
The best time to brush your teeth, eat breakfast and set your alarm (and it's not what you think)
Dentists claim that using your toothbrush straight after breakfast could destroy the enamel on your teeth. So what other timings are we getting wrong in our daily routine? Set your alarm 7.22am We've all heard of entrepreneurs and fitness fanatics who wake at dawn to work out or hit their desks. Should you do the same? Maybe not. A study by the University of Westminster found that people who woke between 5.22am and 7.21am had higher levels of the stress hormone cortisol than those who slept later. They were also more likely to suffer from muscle aches, colds and headaches, and had worse moods. This may be because they miss out on sleep, or because they are working against their chronotype – the genetically programmed tendency to be either a late-to-bed owl or an early-rising lark. Dr Neil Stanley, an independent sleep expert and the author of How to Sleep Well, says that while a 7am wake time is likely to be practical for most people, 'a recent study shows that the most important thing for longevity, even more than duration of sleep, is consistency of wake time.' This means, he says, that we should try to wake up at the same time, 'plus or minus one hour', every day, even at weekends. Brush your teeth Before breakfast You might habitually reach for your toothbrush to scrub away toast crumbs and ensure a clean start to the day. But, says dentist Dr Shaadi Manouchehri, you could also be scouring away your precious dental enamel. She says that when we eat, the natural bacteria in our mouths produce acid to break down the sugar in food. 'So, if you brush your teeth, you are rubbing that acid on the tooth which is a mineral and it can wear it down,' she says. If you hate the idea of heading out without sparkling gnashers, either eat earlier so you can wait until an hour after eating before brushing or brush your teeth first. Eat Breakfast Before 8am In 2023, a study of more than 100,000 people found that eating breakfast after 9am increases the risk of developing type 2 diabetes by 59 per cent compared to people who eat breakfast before 8am. 'We know that meal timing plays a key role in regulating circadian rhythms and glucose and lipid control,' said Anna Palomar Cros, a researcher at the Barcelona Institute for Global Health. 'Our results suggest that a first meal before 8am and a last meal before 7pm may help reduce the incidence of type 2 diabetes,' added Manolis Kogevinas, co-author of the study. While another study showed that 9am breakfasters are 6 per cent more likely to develop cardiovascular disease than those who eat at 8am. They are also more likely to have healthy blood pressure and cholesterol levels. Dr Stanley says eating breakfast is 'a sign to your body it is daytime and is important for regulating your biological clock'. Workouts Morning for sleep and weight loss, afternoon for muscle gain A recent US study has found that, for women, morning workouts between 6:30am and 8:30am reduced abdominal fat and reduced blood pressure. But evening workouts between 6pm and 8pm best enhanced endurance and built muscle. For men, evening workouts were the most effective to burn fat and reduce blood pressure. Generally, studies have shown that scheduling morning exercise could help you stick to healthy exercise habits, shift your body clock to function earlier in the day, encourage more movement and enhance weight loss better than evening workouts. Some research suggests that, compared to exercising at 7pm, a 7am run or other aerobic exercise may be key to better sleep and lower blood pressure. However, Dr Stanley says: 'You can exercise when you like without it affecting your sleep as long as you allow your body temperature and heart rate to return to normal before you go to bed, so have a cool-down stretch, maybe a shower and ease into your bedtime routine.' One study even suggests that, over time, evening exercise can reduce levels of the 'hunger hormone' ghrelin. Make an important decision or ask a favour Between 11am and 12pm Prof Russell Foster, a University of Oxford neuroscientist, is the author of Life Time: The New Science of the Body Clock, and How It Can Revolutionize Your Sleep and Health. 'Our cognitive ability and reaction time peaks between 11am and noon' he says, 'and our mood is also highest at this time, which means it's a good time to ask for a favour or a pay rise.' Daniel Pink, the author of When: The Scientific Secrets of Perfect Timing, says that mood and alertness falls during the sluggish, grumpy post-lunch dip from 1pm to 4pm. And never fire off an important email in the small hours. 'Our cognition at 5am is worse than if we were drunk,' says Pink. Take a nap Between midday and 4pm A recent UK study found that regular naps can help preserve reaction time and memory as we age – as well as leaving us feeling refreshed and more alert. According to the Sleep Foundation, if your lifestyle allows, naps should be between 10 and 20 minutes long, and end before 2pm to avoid interfering with night-time sleep. A Japanese study showed that a 20-minute nap at 12.20 could wipe out the typical afternoon drop in energy. A cup of coffee before your nap can help you wake up naturally, as caffeine takes about 30 minutes to affect your system. Drink coffee After 9am and before 2pm Caffeine blocks brain receptors that detect adenosine, a neurotransmitter in the body which builds up during the day and makes us feel sleepy. However, in the morning, adenosine levels are low, and the alerting hormone cortisol is high, so coffee might not give you the lift you expect. If you want to sleep well, avoid coffee after 2pm as it can take eight hours or more to be fully metabolised. However, Dr Stanley says: 'Some people are more sensitive to caffeine than others, so if you sleep perfectly well after a late-night espresso, keep drinking it. If you know you won't sleep well, skip it.' Eat Dinner 7pm to 8pm Eating late – around 10pm – can increase the risk of weight gain and the risk of diabetes. Scientists in Spain found that people who ate dinner within two hours of bedtime were five times more likely to be obese than early diners. Prof Foster says: 'We are programmed to deal with calories and sugar much better during the first half of the day than the second. If you eat late, you are more likely to lay down calories as stored fat and to store glucose in the liver. It's best to eat a large breakfast and lunch and a small evening meal.' Dr Stanley says: 'We need to lose one degree of body temperature to fall asleep. Burning calories creates heat so a late large meal will warm you up when you should be cooling down. Ideally you should eat no later than three hours before bedtime.' However, you also don't want to go to bed hungry as this can prevent you from dropping off. 'A small bedtime snack is fine,' says Dr Stanley. Go to sleep 10pm to 11pm According to research published in the European Heart Journal, a bedtime between 10pm and 11pm may cut your risk of heart and circulatory disease compared to people who hit the hay later. People who fall asleep after midnight have a 25 per cent higher risk of heart attack and stroke compared to early sleepers. Ideally, we should sleep between six and eight hours a night on average, though, says Prof Foster, 'some people may need as much as 10'. Depending on how much sleep you think you need, you can count back from your wake time to find your ideal bedtime. 'Sleep is the foundation of physical, mental and emotional health,' says Dr Stanley. 'Never underestimate the importance of a good night's sleep.' Tips for sticking to a daily routine Choose the right habits Make it easy to follow Plan it all out (and have a backup plan) Make sure you don't forget things Try 'temptation bundling' It's one thing to understand how to organise your day and quite another to follow through with your plan. First of all, 'make sure it actually works for you and is the right routine,' says Dr Phillippa Lally, an expert in habit formation and a senior lecturer in psychology at the University of Surrey. 'You might well want to exercise each day, but there's no point in telling yourself that you'll go out and run a 10k every morning if you really hate running.' Dr Lally also recommends that you 'remove the friction' involved in getting the different parts of your daily routine done. This means 'making it as easy for yourself as possible': for example, if you want to eat dinner before 8pm, make sure that you have the ingredients you need to cook in your fridge already to avoid a stop at the shops. This is down to having a plan, too. 'Having a plan for your habits makes it an easy decision to follow them,' Dr Lally says. Of course, it's also easy to forget to carry out some habits, like flossing or going for a walk in your lunch break, which you might not be so used to doing daily. The sage advice to set a reminder on your phone does help here, but it can also be helpful 'to tell a friend or family remember to remind you or ask them to do it with you,' says Dr Lally. Try this along with 'temptation bundling', which involves having a rule that you only get to do or have something you enjoy when it comes with the habit you're trying to build, such as listening to a gripping new audiobook only when you hit the gym.
CNN
16-05-2025
- Health
- CNN
What are your questions about fluoride?
Fluoride can help prevent tooth decay by strengthening the protective outer layer of enamel that's worn away by acids formed by bacteria, plaque and sugars in the mouth. Since 1945, it has been added to many US water systems and is also available in toothpaste and other supplements. Recently, some states have banned it from water due to questions about safety, cost and personal choice. The US Food and Drug Administration also said it's taking steps to remove prescription fluoride tablets and drops from the market. What do you want to know about fluoride and its safety and effectiveness? Share your questions with CNN below.
