You can see the pellet that Stanley refers to at the bottom of your drink container. It seals those layers together where they all meet at the bottom of the bottle, in a process called lead soldering. Technically, the vessel does contain lead, but it’s enclosed with stainless steel and should never come in contact with your drink or skin. However, should you drop the water bottle, or if it otherwise gets damaged, and this piece of steel comes loose, there’s a chance the lead can be exposed to your skin.
Lead is a naturally occurring toxic metal. The World Health Organization (WHO) cites that there is no safe level of lead exposure. “Once lead enters the body, it is distributed to organs such as the brain, kidneys, liver, and bones.” High levels of lead exposure can be fatal. With lower levels of exposure—which can happen with a microscopic amount—lead poisoning in adults can cause nerve disorders, decreased kidney function, and fertility issues. In children, it can cause developmental delays and seizures. The WHO says children are “particularly vulnerable to lead poisoning because they absorb four to five times as much ingested lead as adults.”
“Lead is ubiquitous in the environment, so low levels of daily exposure are a fact of life,” says Jane Houlihan, national director of science and health at Healthy Babies Bright Futures. “Exposures and risks add up day to day from lead in food, water, house dust, and soil. This makes it all the more important for companies to keep lead out of consumer products. Children don’t need another potential source of lead in their lives.”
What Do Other Brands Use?
Lead soldering is low-cost and easy to use. However, alternative methods are available. Several of the reusable water bottle companies we reached out to do not use lead in their manufacturing process. Here’s the list:
Owala, which makes popular bottles like the FreeSip and a Stanley-dupe tumbler, says it has never used lead in its manufacturing process. “The production of vacuum-sealed containers using lead-free solder is more costly and complicated. However, we made a commitment from day one with Owala to use lead-free solder on our bottles,” an Owala spokesperson says.
Hydro Flask, another internet-famous water bottle company, stopped using lead solder more than 10 years ago. “By mid-2013, the lead was out of the Hydro Flask production process because the brand designed a proprietary sealant, TempShield,” a Hydro Flask spokesperson says.
Klean Kanteen also forgoes lead, instead using a noncrystalline silica bead to create its vacuum-insulated bottles. “The process, using silica instead of lead, is the same except higher heat is required to melt the silica,” says Rich Haver, the company’s director of global operations. While some forms of silica can be dangerous if very fine particles are inhaled—sand is made from crystalline silica, so even finer than that—this doesn’t apply to noncrystalline silica glass. “Silica in its noncrystalline form does not have the same respiratory health properties as crystalline silica,” says Marty Cohen, a teaching professor in the Department of Environmental and Occupational Health Sciences at the University of Washington.
MiiR is the only company, of the ones we contacted, to use lead in its manufacturing process. According to its website, “This pellet does contain lead for manufacturing efficiency, waste reduction, and to ensure a complete seal. For these reasons and because there is zero lead exposure, MiiR utilizes this process with confidence.”
The following companies did not respond to our requests for comment: Yeti, S’well, HydroJug, Greens Steel, and LifeStraw. (Sigg responded but has not given us an answer yet; we’ll update this story when they do.)
An AI-powered test that claimed to be “clinical grade” listens for signs of stress in people’s voices. But it provides inconsistent results when tested on the same person twice, according to a study
This big-budget series from David Attenborough and the BBC Studios Natural History Unit takes a closer look at the flora and fauna of the UK and Ireland. Warring capercaillie and the sex lives of ash-black slugs are two highlights.
Each episode of Earth delves deep into the history of our planet, from the worst-ever mass extinction to the rise of humans, and is replete with cutting-edge scientific research.
A still from Earth of an 8-metre tall fungus, Prototaxities, that towered over plants 430 million years ago.
Michael J. Fox, best known as the star of the Back to the Future films, was diagnosed with early-onset Parkinson’s disease at just 29 years old. His documentary about living with the condition is moving but never mawkish.
Mathematician Hannah Fry presents this addictively interesting series, which returned in 2023 to teach us all about the innovations underpinning everyday life, from passports to vacuum cleaners.
Hannah Fry in her “addictively interesting “The Secret Genius of Modern Life”
It can be difficult to look the world of emergency medicine straight in the eye, but this unflinching documentary about New York’s frontline healthcare workers is must-see viewing.
Another entry from David Attenborough, this beautifully animated series explores the weirder, wilder side of dinosaurs and their contemporaries. With its emphasis on recreating the feel of a classic nature documentary, you will feel like you are really inhabiting the prehistoric world.
Foodborne illnesses affect 48 million people in the US every year. This documentary takes aim at the industries fuelling these outbreaks, with shocking revelations.
Ella Glendining, who was born with no hip joints and short femurs, had never met anyone with the same rare condition she has. The community she finds throws the discrimination she faces elsewhere in life into sharp relief.
Ella Glendining in the documentary Is There Anybody Out There?
When it comes to mainstream nature documentaries, too few are bold enough to explicitly connect Earth’s natural beauty to the threats it faces from climate change. Our Planet II is a refreshing deviation.
Only one episode of The Color of Space, NASA’s seven-part series about Black astronauts at the agency, has been released, but it is already a highlight of the new streaming service NASA+. Episode one is about Charlie Bolden, who became NASA’s first Black administrator.
This eclectic four-part series tackles drone warfare, the James Webb Space Telescope, Homo naledi and an ancient necropolis – perfect for mystery fans who are seeking variety.
If you have ever lit up a joint and craved a snack soon afterwards, you were probably experiencing the “munchies”. Stimulating appetite is one of marijuana’s best-known and most puzzling side effects. But why does weed make you want to chow down?
The psychoactive compound in cannabis, delta-9-tetrahydrocannabinol, or THC, is what gets users high. However, THC also spikes our appetite by tapping into the body’s endocannabinoid system, a complex cell signalling network that controls everything from emotion and sleep to …
I RECENTLY scoured my kitchen looking for trouble, and I found plenty. There was a packet of instant noodles in a cupboard. Tins of baked beans and a box of muesli. In the fridge, a Jamaican patty, ketchup, hummus and probiotic yoghurts. Over in the bread bin, a loaf. I didn’t dare peek in the freezer.
These foods are part of my normal diet, which I don’t think is especially unhealthy. But by eating them, I may be opening myself up to obesity, heart disease, a fatty liver, cancer and more. That’s if you believe the increasing worries over ultra-processed foods (UPFs) and how bad they supposedly are for our health.
But amid the warnings, there are still many open questions. Are UPFs really bad for you? If so, why? In fact, what exactly are ultra-processed foods anyway? Sprinkle in the myriad social and economic issues intimately associated with the purchase of said foods (see “Ultra-processed do’s and don’t’s”, below), and it is no wonder everyone is so confused.
In an attempt to get some clarity on the matter, I have spoken to researchers at the forefront of the debate. And while there are no clear answers on UPFs, it is possible to navigate this nutritional quagmire.
Humans have been processing food for millennia to make it tastier, more digestible, more resistant to decay and more convenient. Salting, drying, fermenting, pickling and smoking were invented to preserve foods; milling produced flour to bake bread. Cooking turned unpromising or toxic raw ingredients into tasty, safe and nutritious meals.
During the industrial revolution, however, mechanisation entered the food system. In 1802,…
THEY were considered flukes. Older people found upon their deaths to have brains full of the plaques and tangles associated with Alzheimer’s disease, yet who had shown no signs of cognitive decline while alive. But then more cases appeared, and yet more. Something was protecting these people whose mental faculties remained bright, despite them facing the same destruction in their brain as others with memory loss, confusion and other symptoms of dementia.
As more brains were analysed, it was discovered that these cases aren’t rare. Up to 30 per cent of older people have enough plaques and tangles to be…
There are TikTok hashtags with millions of followers, endless column inches over celebrities’ waistlines and streams of media coverage when trial results come out. It is rare that a new medicine gets so much attention. Then again, it is even rarer that a licensed drug causes safe and rapid weight loss with minimal effort.
A year ago, most people hadn’t heard of semaglutide, a drug developed to treat type 2 diabetes around a decade ago under the brand name Ozempic. Then, in 2021, it was approved in the US as a weight-loss aid under the name Wegovy. The medicine can cause people to lose a whopping 15 per cent of their body weight.
The impact of this new class of medicines could be unprecedented – potentially bringing to an end the world’s growing obesity epidemic. “I don’t think it’s fully sunk in yet,” says Jonathan Campbell at Duke University in North Carolina, who investigates how these drugs affect the body.
For one thing, Wegovy was just the start. The next generation of these drugs is in development and will be cheaper, easier to use and, crucially, even more potent. What’s more, emerging evidence suggests Wegovy and its ilk work better when given at a younger age, so doctors are exploring their use in teenagers and young children. This raises the prospect of switching from obesity treatment to prevention. “We have watched the obesity landscape change dramatically over the last 40 years,” says Campbell. “Now, maybe we’re at a turning point where that goes backwards.”
Why obesity is on the rise
The rise in obesity has been happening since about the 1970s…
THE bouts of terrible pain began further back than Victoria Gray can remember. Her grandmother would try to ease the discomfort with hot towels and medication, but it was fruitless. “I was born having to endure pain,” she says. “It was a life that I felt wasn’t worth living.”
Gray has an inherited condition known as sickle cell disease, which causes red blood cells to form an abnormal “sickle” shape that can block capillaries, causing pain and sometimes organ damage. As Gray aged, her pain got worse. On one occasion, she temporarily lost the use of her arms and legs. By her 30s, Gray required in-home care. So, when she was offered the chance to become the first person to receive an experimental CRISPR gene-editing treatment, she took it.
Today, four years after this took place, she no longer has episodes of pain and works full time. “Now my life is full of optimism,” she says.
The treatment involved will probably be given the green light by regulators in the US, UK and Europe soon, which will make it the first CRISPR therapy to be approved. It won’t be the last.
There is now no doubt that this technology – used to edit genes – can treat and potentially even cure a huge range of conditions. The only question is, just how far can it go? Will it be an expensive therapy used only occasionally? Or will it become so widely used that many of us will be getting a CRISPR jab to, say, lower our cholesterol levels and enable us to live longer, healthier lives?
The left side of William McElligott’s face is more wrinkled than the right after being exposed to more sunlight
NEJM
ON HER 120th birthday, Jeanne Calment – generally regarded as the oldest person ever to have lived – proved she still had her wits about her: “I’ve only got one wrinkle,” she wisecracked, “and I’m sitting on it.” Funny, but untrue. The Frenchwoman was, by then, extremely wrinkly. On the Fitzpatrick Wrinkle Scale, she would have been a shoo-in for the top category, with deep wrinkles and discoloured skin that had lost its elasticity.
Quelle surprise. She may not have been as old as she claimed, but she was at least 97. Anybody who lives to 100 or so can expect the same. Historically, this has been regarded by many as a purely cosmetic problem. Wrinkles, sags and bags are, in some cultures, considered unsightly or an unwanted sign of how old we are. Right or wrong, that has led to a centuries-long battle to fill them in or smooth them over. More recently, however, the war against wrinkles has moved onto a more urgent footing. Aged skin is much worse than young skin at all the vital things it does to help maintain your health.
Moreover, emerging evidence suggests that, as skin ages, it releases a chemical cocktail around the body that could drive premature ageing of other organs. “If your skin is getting older, you are getting older inside, so be careful,” says Cláudia Cavadas at the University of Coimbra, Portugal. In other words, wrinkles may not just be…
SCIENTIFIC revelations come from the unlikeliest of places. Like a rat, in a lab, doing a “downward dog” stretch.
According to the people who found a way to get rats to do yoga, these creatures benefit from a good stretch as much as we do. In the process, they are revealing the true significance of a body tissue that has been overlooked by science for centuries.
The 19th-century anatomist Erasmus Wilson called this tissue – now known as fascia – a natural bandage. In dissection, that is exactly what it looks like: sheets of white, fibrous connective tissue that are strong yet flexible and perfect for keeping muscles and organs in place. They are also sticky, gloopy and get in the way of looking at the muscles, bones and organs they cover. Which explains why, for years, anatomists cut this tissue off, chucked it away and thought little more about it.
Recently, though, researchers have begun to take a fresh look at fascia and are finding that it is anything but an inert wrapping. Instead, it is the site of biological activity that explains some of the links between lifestyle and health. It may even be a new type of sensory organ. “There appears to be more going on in the fascia than is commonly appreciated,” says Karl Lewis at Cornell University in Ithaca, New York.
We are now realising that a better understanding of this ubiquitous tissue is sorely needed. If we manage to figure it out, it has the potential to provide new ways to tackle many common yet hard-to-treat conditions, from immune dysfunction to chronic pain.
One difficulty with studying fascia is that there is disagreement about what it actually is. It comes under the umbrella of connective tissue, which, at its broadest definition includes not only tendons and ligaments, but also bone, skin and fat.
Most fascia researchers, however, understand it to be sheets of tissue made up of strong collagen fibres and more stretchy elastin fibres. In many places, these fibrous sheets are separated by “areolar” or “loose” fascia, a form that contains fewer fibres and with the gaps between fibres filled with a slimy substance that allows the surrounding layers to slide over each other. The main ingredients of this slippery soup are hyaluronic acid, for lubrication, and proteoglycans, molecules that provide cushioning. The fascia fibres and the soup are both secreted by specialised cells in the tissue – fibroblasts and the recently discovered fasciacytes.
Holding us together
If you were to cut into the body, you would find two obvious layers of this natural cling film: the superficial fascia, which sits directly under the skin, and the deep fascia, which wraps muscles and organs and connects them to each other. Some researchers, however, extend the definition to include the visceral fascia, which lines the body cavity and divides it into compartments for different organs, and also thin layers of connective tissue that line pretty much every part of the body. By this definition, fascia forms a network that pretty much holds us together (see “A body-wide network“).
Remarkably, until the early 2000s, no one had studied this common tissue in detail. Among the first to do so was Carla Stecco, an orthopaedic surgeon and anatomist at the University of Padova in Italy. She started studying fascia 20 years ago when her father, a physiotherapist called Luigi Stecco, invented a form of physical therapy called fascial manipulation, which he claimed could treat everything from headaches to muscle and joint pain. His system is now one of many physical therapies that hinge on the idea that fascia can become stiff, and that it can be “released” through massage.
The only problem was that there was no evidence for or against the idea that physically manipulating the body did anything specifically to the fascia, or that this would affect pain. And as Carla Stecco soon discovered, there wasn’t even a body of literature explaining, in detail, what fascia actually was. It wasn’t even known if it had nerves associated with it, she says.
Since then, she and others have shown that fascia is indeed rich in nerves, and that the information that these relay varies throughout the body. Superficial fascia contains nerves that specialise in sensing pressure, temperature and movement. Deep fascia is involved in proprioception, the body’s sense of its position in space, and nociception, the sensing of pain.
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Because of this sensory role, some researchers say that fascia should be considered a new organ, one that is specialised for communication about the body’s internal state. Robert Schleip at the Technical University of Munich in Germany recently estimated that an adult’s fascia contains approximately 250 million nerve endings, similar to, or slightly more than the skin. “It is beyond any doubt our richest sensory organ,” he says. Others are more cautious. “It’s plausible, but there is a strict definition for an organ to do with material organisation, cell types and function, so it sounds like it’s a candidate,” says Lewis. “But it’s early days for making that determination.”
Organ or not, there is evidence that deep fascia specialises in a different kind of message to other bodily tissues. Experiments in which healthy human volunteers had painful injections into their skin, muscles and fascia showed that while nerves in the skin and muscles produce focused, localised pain, the network of nerves in fascia is linked to a radiating pain, one that is more difficult to pinpoint. This kind of diffuse pain is a feature of several chronic pain disorders, including fibromyalgia, which some studies have linked to inflammation in the fascia. It is also a feature of post-exercise soreness, which has long been blamed on damage to the muscles, but which some researchers now think has more to do with injury or inflammation in the fascia.
The bad news for anyone with inflamed fascia is that if it continues for too long, the body responds by altering the composition of fascial nerves to become more sensitive to pain. In rats, the percentage of nociceptive fibres – pain receptors that respond to harmful stimuli – in the fascia increased from 4 per cent to 15 per cent following chronic inflammation of deep fascia in the lower back.
This could help to explain why lower back pain is so difficult to treat. Despite being one of the most common causes of work absence and overall movement restriction, 85 per cent of cases worldwide are classified as non-specific, meaning the exact cause can’t be established.
Given what we now know about nerves in the fascia, the thoracolumbar fascia, a diamond-shaped, multilayered structure in the lower back in which different layers connect to different muscle groups in the trunk, is starting to look like a good place to put the blame for this back pain. “The thoracolumbar fascia is like a big receptor that is able to feel the tension coming from the upper limbs, the spine and the abdomen,” says Stecco. The sensory neurons in the fascia may respond to this tension by registering it as pain.
Fascia is a connective tissue made up of fibres of the proteins collagen and elastin
Prof. P. Motta/Dept. Of Anatomy/University "La Sapienza", Rome/Science Photo Library
On top of nerve changes, inflammation in the loose, areolar fascia that is found between fascial layers can make matters worse. Helene Langevin at the US National Institutes of Health in Maryland used ultrasound imaging of the lower back to show that people with chronic lower back pain had thoracolumbar fascia that was 20 per cent stiffer than those without this pain.
This stiffness seemed to be explained by multiple layers of tissue becoming stuck together, stopping the loose layer from sliding. Her studies in pigs have backed this up, showing that even after an initial injury has healed, a lack of movement in the lower back can be enough to keep the fascia stiff and to cause adhesions, where two layers become physically linked by new collagen fibres. This, other studies suggest, restricts movement, not only in the fascia immediately surrounding the stiff spot, but also in connected regions nearby. In particularly severe cases, fascial layers can become stuck into one immobile block that runs from the superficial fascia to the deep fascia and into the muscle.
Injury and inflammation aside, there are many other reasons why fascia may become stiff. Schleip’s research hints that activation of the sympathetic nervous system, which is involved in the body’s fight-or-flight response, causes the fascia to contract by prompting the fibroblasts within it to transform into myofibroblasts, cells that are part of the inflammatory response to injury, often seen in joint-related problems such as frozen shoulder.
The details of how exactly fight-or-flight stress leads to stiffness are still being worked out, but Schleip says that adrenaline seems to increase the expression of an inflammatory substance called TGF-beta. This is then stored in the loose fascia in preparation for the next time the body is stressed. When this happens, fibroblasts “drink [TGF-beta] and they become myofibroblasts in a few hours”, he says. “And then they are four times as strong as before. They are contraction machines. So, adrenaline can make fascia stiffer.”
In fact, the list of things that affect fascial stiffness is getting longer all the time. “Oestrogen is able to create a fascia that is more elastic,” says Stecco. “The fascia is a very dynamic tissue that is able to answer to hormonal input, chemical input and mechanical input. Altogether, that defines if our fascia is elastic or rigid.”
On the plus side, this dynamic nature of fascia suggests that lifestyle changes could help to reverse problems related to it. One promising intervention under investigation is stretching. In samples of rat tissue, Langevin found that stretching causes changes to the fibroblasts that make up the matrix of the loose fascia. She says they expand several fold and become longer and flatter. “Stretching the tissue allows it to relax,” she adds.
Stretch it out
Other studies by Langevin with pigs showed that stretching the lower back for 5 minutes, twice a day, not only reduced the size of an area of inflammation, but also seemed to induce a series of anti-inflammatory chemical events from the fascia. This is a promising finding because chronic inflammation has been linked to pretty much every modern ailment going, from heart disease and diabetes to cancer and depression.
A team at Harvard Medical School is conducting a trial in people to find out if the same is true in humans. A pilot study completed in late 2021 showed that healthy volunteers who undertook an hour-long stretching session had altered levels of immune system molecules called cytokines, compared with those who didn’t stretch, suggesting that there is a regulation of inflammation after stretching.
Future studies will assess whether levels of resolvins, chemicals made by the body that turn off inflammation, also increased, as has been seen in rat and pig stretching studies. If so, stretching could prove useful for reducing cases of more widespread chronic inflammation, which can be triggered by long-term stress, obesity and bad diet.
As for physical therapies that focus on fascia release, such as massage, it is unclear whether they have the same cellular and anti-inflammatory effects as stretching seems to, or whether they simply make temporary changes to the fascia. It could be, for example, that manual therapies warm the tissues, which has been shown to make the fascia matrix less viscous, temporarily allowing the layers to slide more easily. Langevin sounds a note of caution, that until more is known about what happens during these therapies, it isn’t clear what, if anything, they do to the fascia, or anything else.
In order to turn fascia research into evidence-based treatments, this tissue will also have to overcome its image problem among scientists. This dates back to the 1940s and 50s, when medical researchers were paying little attention to the stuff, and it became central to an alternative approach to health invented by the late biochemist Ida Rolf. Her method, which she called structural integration, but which is better known as Rolfing, is a mixture of physical therapy and claims about alignment of bodily energy fields. Since then, fascia has become a buzz word in all kinds of alternative therapies.
Stecco, however, thinks that it is high time for the mainstream medical profession to start paying attention to this tissue. She would like fascia to be recognised as important to many areas of medicine, and as a window into our overall health. This, she says, would be “the true revolution of the fascia”.
A body-wide network
Our understanding of how fascia affects health (see main story) depends on where you draw the line between where it begins and ends in the body.
Some people think that as well as the distinct layers of this tissue found under the skin and surrounding muscles, the term should also cover the interstitium: the fluid-filled connective tissue that lines every organ, muscle fibre and blood vessel.
If that is correct, the fascia makes a whole-body network of fluid that could function both as a shock absorber and an immune network relevant to inflammatory disorders, scar formation and the spread of cancer.
The true nature of the interstitium only became apparent in 2018 when a study by Neil Thiese at the Icahn School of Medicine at Mount Sinai, New York, and his colleagues used a new microscopic technique to look at its structure in a living person undergoing a biopsy. In the past, it was only possible to see this tissue by removing it and squashing it on a microscope slide. When seen in living tissue, what had previously looked like a dense tangle of fibres actually had a sponge-like structure filled with fluid that drained into the lymphatic system, part of the body’s immune set-up.
The team suggested that physical movement may help keep this fluid healthy, whether due to the pumping of the heart, the movement of the digestive tract or physical movement of the body. “It seems that no such spaces are static,” says Thiese. This discovery opens up the possibility that the body is connected in ways that we are only beginning to understand and that movement is required to keep this tissue healthy.
