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Is a universal cancer test possible?

Research published in Nature Communications suggests that it might be.

cancer-testScientists, based at the University of Queensland, have discovered something they believe to be common to all cancers – a unique nano-scaled DNA signature.

The scientists used this unique signature to develop a test that might detect cancer from any tissue type, including blood.

Dr Laura Carrascosa, a researcher at the University of Queensland, said: “There’s been a big hunt to find whether there is some distinct DNA signature that is just in the cancer and not in the rest of the body.”

To find this distinct signature the researchers assessed molecular patterns displayed by methyl groups that are usually distributed evenly across a healthy cell’s DNA. Methyl groups serve as signals to control which genes are turned on or off at any given time and are very important to cell function.

The team discovered that in a cancer cell the genome is almost bare, except for intense clusters of methyl groups at specific locations.

This signature, named by the scientists as the cancer ‘methylscape’ appeared in breast, prostate and colorectal cancer cells.

“Virtually every piece of cancerous DNA we examined had this highly predictable pattern,” said Professor Matt Trau, lead researcher at the University of Queensland.

It was then found that these clusters of methyl groups cause cancer DNA fragments to fold into 3-D structures that will stick to gold nanoparticles.

The researchers made use of this curious finding to develop the reported cancer detection method. They used gold nanoparticles that change colour depending on whether the 3D nanostructures associated with cancer DNA are present or not. The resulting test is simple, cheap and can provide results in less than 10 minutes and is believed to potentially be a radical new approach to cancer detection.

“Our technique could be a screening tool to inform clinicians that a patient may have a cancer, but they would require subsequent tests with other techniques to identify the cancer type and stage,” Carrascosa said.

The test has been reported to have a sensitivity of around 90%, so would detect 90 in 100 cases of cancer.

Dr Ged Brady, of the Cancer Research UK Manchester Institute, commented: “This approach represents an exciting step forward in detecting tumour DNA in blood samples and opens up the possibility of a generalised blood-based test to detect cancer. Further clinical studies are required to evaluate the full clinic potential of the method.”

Gene-edited babies – how far is too far?

Claims by scientist He Jiankui last month of the creation of the world’s first gene-edited twins, shocked and appalled the global scientific community.

gene-edited twinsHis experiment still hasn’t been fully substantiated, but the way it was conducted, the implications of his research and the way it was announced, has caused worldwide controversy.

“We heard an unexpected and deeply disturbing claim that human embryos had been edited and implanted, resulting in a pregnancy and the birth of twins,” read a statement released by the organising committee of the Second International Summit on Human Genome Editing in Hong Kong.

“Even if the modifications are verified, the procedure was irresponsible and failed to conform with international norms.”

He Jiankui is an associate professor at the Southern University of Science and Technology in Shenzhen, an institution that denied any knowledge of his research.

Xu Nanping, Vice-Minister for Science and Technology told the Chinese state-owned network CCTV: “The genetically edited infant incident reported by media blatantly violated China’s relevant laws and regulations. It has also violated the ethical bottom line that the academic community adheres to. It is shocking and unacceptable.”

CRISPR is a gene-editing tool, that can be used to control which genes are expressed in an organism. Through its use, it’s possible to delete undesirable traits or add them to an organism’s genome.

It has previously been used in the lab for editing human embryos, but the created embryos have never been implanted and allowed to develop into gene-edited babies. The novel nature of this procedure, the lack of testing and disregard of the proper protocol has raised concerns with many in the science community.

Were the parents properly informed of what was happening? Did they understand the implications fully? Could the technology have unwanted side effects? Is it ethical? These are just a few of the questions currently circulating.

The edited embryos also have germline mutations, meaning that the edited genes of the twins could be passed on to any children that they may have.

The creation of the CRISPR edited twins has shown the potential threat and power of technology that isn’t carefully regulated and monitored. And it serves as a call to action for scientists and regulators across the globe to think more carefully about gene editing technology.

But is the answer simply to suspend gene-editing efforts? Or could this create even more problems with scientists going underground to try out this new tech?

Written by Angharad Baldwin

 

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Top Science News

UPDATE: The Kilogram Redefined

As was mentioned in our October 20th top science news blog, the General Conference on Weights and Measures in Versailles, France has decided to redefine the kilogram, along with the ampere, the kelvin and the mole.

IPK
The international prototype of the kilogram (IPK), courtesy of the BIPM

For more than 130 years the International Prototype Kilogram (IPK), a cylinder of a platinum alloy stored at the International Bureau of Weights and Measures (BIPM) in France, has been used to define the kilogram. Several close replicas of the IPK have been made and distributed around the globe, however, discrepancies have been found between the IPK and its replicas as they have deteriorated over time. Although the discrepancies are minute, this has a big impact when scientists are measuring at a tiny scale, therefore a more robust solution is necessary to ensure the stability and accuracy of this measurement over the longer term.

Planck’s constant, which enables weight to be related to electrical current will be used to measure the kilogram. This is done because electromagnets generate a force, this force is directly proportional to the amount of electrical current going through its coils, therefore, there is a direct relationship between this force and electricity (Planck’s constant).

To measure Planck’s constant, and therefore the kilogram, the Kibble Balance, a set of super-accurate scales developed by Dr Bryan Kibble, will be used. The Kibble Balance has an electromagnet that pulls down on one side of the scales, while a weight, in this instance a kilogram, is placed on the other side. The electrical current going through the electromagnet is then increased until the two sides are balanced, giving an incredibly accurate calculation of Planck’s constant.

Using the IPK meant that every few decades the replica kilograms had to be measured against the original. With the new method, coming into force on 20th May 2019, anyone with a Kibble Balance will be able to check their weights any time.

An InSight into Mars

NASA has reached another milestone with its InSight spacecraft blazing through the Martian atmosphere and landing safely on the surface of the Red Planet on Monday 26th November. The lander touched down near Mars’ equator on the western side of a flat, smooth expanse of lava called Elysium Planitia. The team leading InSight’s entry, descent and landing, based at NASA’s Jet Propulsion Laboratory in Pasadena, California, and at Lockheed Martin Space in Denver, had pre-programmed the spacecraft to perform a specific sequence of actions to make this possible.

NASA's InSight lander
An illustration showing a simulated view of NASA’s InSight lander about to land on the surface of Mars. Image credit: NASA/JPL-Caltech

Only about 40% of missions sent to Mars globally have been successful. This is because of the extreme conditions found on Mars, including an atmosphere of only 1% of Earth’s, meaning there is very little friction to slow down the spacecraft. A parachute and retrorockets were used to decelerate the spacecraft. InSight hit the Martian atmosphere at 12,300 mph (19,800 kmph), and the whole sequence until touching down on the surface took only six and a half minutes.

InSight’s two-year mission will be used to study the deep interior of Mars so that we can learn how rocky planets, including Earth and the Moon, formed and how they could have developed so differently from one another.

Potential Peanut Allergy Treatment

A severe food allergy of any kind is life-altering, not only for the sufferer but also for their families, with the best practice being total avoidance. However, this isn’t always an easy option. Research sponsored by Aimmune Therapeutics and published in the New England Journal of Medicine has shown some advancement in the potential treatment of peanut allergy.

NutsThe trial involved nearly 500 children with a severe peanut allergy and successfully desensitised two-thirds of those who completed the trial. The study involved gradually increasing a tiny dose of peanut protein over a period of six months. After one year of treatment, the children could eat the equivalent of three to four peanuts.

However, several adverse effect were uncovered during the research with patients suffering from high rates of allergic reactions including hives and stomach pains as the dosage of peanut protein was increased. Furthermore, over 20% of the patients dropped out of the trial. The potential cost of the treatment may end up outweighing the benefits as patients would have to keep taking the medication to maintain tolerance levels, possibly for life.

Written by Jeanne Kroeger

Breaking the Barriers

Breaking the Barriers: Achieving Gender Parity in the Chemical Sciences

Welcome to the first in the series of Science London’s look into issues of diversity and equality in STEM.

Gender equality is still something we as a society are striving towards, but different industries have their own struggles and so it is important to see how these sectors are trying to achieve gender parity.

The Royal Society of Chemistry (RSC) launched their report Diversity Landscape of the Chemical Sciences earlier this year and have now released a follow up with: Breaking the Barriers. The report looks at the lack of retention and progression of women in the chemical sciences, but it also examines issues of gender discrimination, racial discrimination, harassment and bullying.

The headline figure from the report states that 99% of female chemists in UK academia can evidence the lack of retention and progression of women – as can 94% of men. This has huge consequences for the industry as well as affecting the pipeline of young talent. Presently, women make up only 44% of undergraduate students in the chemical sciences. This figure decreases to 39% of PhD students and only 9% when looking at the proportion of women who are professors.

The issue of women’s retention and progression is particularly pronounced in the chemical sciences in comparison with other scientific disciplines. Dr Helen Pain, Deputy Chief Executive at the Royal Society of Chemistry, said: “Talented, hard-working people should not be made to feel that they cannot progress in their field. Yet it is clear from our research in the community that barriers exist when it comes to progression and retention in the chemistry profession, most acutely in academia. As the UK’s professional body for chemical scientists, we are using our position, influence and connections to take the lead, push for accountability and develop best practice.”

Three key barriers were identified by the report:

  • A poor management culture, including unequal workloads, a lack of recognition opportunities, and bullying and harassment.
  • The way research posts are funded creates uncertainty and unnecessary pressure.
  • Practical barriers, such as a lack of opportunities for part-time and flexible working.

The benefit of addressing retention and progression of women is clear to the community itself. More diverse teams will produce better science and will deliver economic benefits through increased productivity. To tackle these barriers, the RSC has developed a five-point action plan, including launching annual recognition for chemistry departments that demonstrate significant progress in inclusion and diversity, improving the exchange of best practice between peers.

Professor Dame Carol Robinson, the first female Professor of Chemistry at the Universities of Oxford and Cambridge, is President of the Royal Society of Chemistry. She added: “The culture within academia and industry can be problematic for women but there is also an impact on work/life balance for men and we should not overlook this. It is essential that every part of our community works together to make sure chemistry really is for everyone.”

The full report can be viewed online.

Written by Jeanne Kroeger

Top Science News

Post-Halloween bummer for Freakshake fans

For anyone who isn’t familiar with the concept of Freakshakes, imagine what a kid would do to a milkshake when given the chance and free reign over the entire candy department of a store. Freakshakes not only contain the creamy milky goodness of a traditional milkshake but are adorned with additional candies, chocolates, syrups, whipped cream, sprinkles and pieces of cake. Literal big slices of cake at times. It is therefore not surprising that many of them come in at more than half the daily calories recommended for adults.

FreakshakeResearchers tested 46 Freakshakes from different suppliers and all fell in the red label category for sugar, including examples such as the “Unicorn Freakshake” available at Toby’s Carvery, containing 39 teaspoons of sugar and 1,280kcal. The problem with those numbers becomes apparent when one has a look at the recommended MAXIMUM intake of sugar for an adult: 6 teaspoons. While the shakes definitely are Instagram worthy and fun to maybe share as an occasional treat, the campaign group Action on Sugar now demands a ban on any freak- or milkshake that contains more than 300kcal. Public Health England agrees and is running a sugar reduction programme which is part of the government’s childhood obesity plan and attempts to incentivize businesses to cut sugar by 20% by 2020, including milkshakes and the like. The Freakshake trend is particularly worrying, as obesity rates and incidences of diabetes type 2 are increasing in the UK, with more than 1 in 17 people in the UK already suffering from diabetes. The amount of sugar and calories found in a single serving of a Freakshake is to a certain extent frightening and between all the Halloween candy and the upcoming Christmas feasting period, we should really reconsider if we are in need of monstrous milkshakes.

Obesity = Cancer, but why?

The link between obesity and cancer has been well established and over 1 in 20 cancer cases are caused by excessive weight. This means that only short of smoking, obesity is the number one cause for cancer in the UK. cancerIntriguingly we don’t exactly know why, but researchers have suggested overproduction of hormones and insulin as possible triggers of cancer development. Researchers from Trinity College Dublin have now identified one definitive way in which obesity can cause cancer, by clogging up our immune system with fat. The paper, published in the journal Nature Immunology, reports that one type of immune cells, called Natural Killer (NK) cells are literally clogged up by fat and cannot function properly anymore. While they are still able to recognise tumour cells, their ability to destroy the tumour cells is diminished, thereby rendering them useless for fighting cancer. The researchers used human NK cell cultures, as well as mouse model organisms and found that NK cells failed to reduce tumour growth in obese mice. Interestingly, they showed that by adding a compound that breaks down the clogged up fat in the NK cells, their protective function can be restored. However the researchers suggest that, rather than taking drugs which might come with side effects, simple weight loss would do the trick. So, step away from the Freakshake.

Britain’s got Science

The Bank of England announced that the new polymer £50 note is coming after all and they have asked the public to hand in their suggestions for who they want to see on the new note, besides Her Majesty.

moneyThere are currently about 330 million £50 notes in circulation, so whoever will be portrayed on it will surely receive attention from the public. The relatively new polymer banknotes were first introduced in September 2016, starting with the new £5 notes portraying the politician Winston Churchill. The reasoning behind the introduction was that they are generally harder to counterfeit, cleaner and more resistant to damage. While you might think that introducing more plastic into the world is not such a good idea, the Bank of England argues that the polymer bank notes are actually better for the environment as they last longer than the old paper money. One of the downsides is the use of animal fat in the production of polymer notes, but most people probably prefer this to the alternative of palm oil, which is highly unsustainable for our environment.

Everyone who is interested in making a nomination can go to their website and fill in a short form to make their wishes known. The first condition: it has to be a British scientist!

With the current climate of mistrust in Science and “experts”, this is a good opportunity to highlight some important scientists who are not widely known, but have made huge contributions to the advancement of the Sciences. The other conditions are that the individual must be dead and from the field of astronomy, biology, biotechnology, chemistry, engineering, mathematics, medical research, physics, technology or zoology.

So, if you have anyone in mind you would like to see represented on the new money, go ahead and let the Bank of England know!  You can nominate your favourite dead scientist until Friday, the 14th of December.

Written by Charlott Repschlager

 

Top Science News

Having your appendix removed might protect you from Parkinson’s disease

parkinson'sWhere does Parkinson’s disease start? The answer to this seemingly simple question might be very different than we thought. The condition seems to originate in the gut, rather than the brain, and travels along nerves, ultimately causing brain damage. New research is pinpointing the origin of Parkinson’s more precisely. In a study published in Science Translational Medicine Bryan Killinger and his colleagues show that the toxic compound which causes Parkinson’s can be found in the appendixes of healthy people. Furthermore, having your appendix removed early in life seems to protect from Parkinson’s.

The degenerative condition causes motor difficulties such as tremors, muscle stiffness and slowing movement. In the brains of Parkinson’s patient’s synuclein, a protein whose function in the healthy brain is not clear, aggregates into clumps and causes the loss of nerve cells. This sets off a domino effect which leads to more clumping and the loss of more and more nerves.

The new study shows, that the appendix, which also plays a major role in the regulation of gut bacteria, is a reservoir of clumping synuclein, even in healthy individuals. To answer the question, if appendectomies would protect patients from the condition, Viviane Labrie of the Van Andel Research Institute in Michigan conducted the largest and longest study on this to date. The researchers analysed healthcare records of 1.6 million Swedish people over the age of 52. They concluded that patients who had their appendix removed had a nearly 20% lower risk of developing Parkinson’s.

It is unclear if removing the appendix at an early stage of the disease might slow or stop its progress. With synuclein aggregates being found in the appendixes of healthy individuals, the search for the factors that tips the scales towards Parkinson’s disease in some patients continues.

The stars of a new dinosaur blockbuster: blind, grazing and nocturnal?

The largest bird alive today is the ostrich. A large male ostrich can be up to 9.2 ft (2.8 m) tall and weigh over 344 pounds (156 kg). But when it comes to the heavyweight champion of the bird world, no one beats the recently discovered elephant bird species Vorombe titan, an extinct flightless bird from Madagascar. Researchers estimate that this bird weighed 1400 pounds (650 kg) and while height estimates are harder to make, up to 12 ft seems possible.

ostrichIn a new study published in the Proceedings of the Royal Society B, Christopher R Torres and Julia A Clarke digitally reconstructed two elephant bird brains (Aepyornis maximus and Aepyornis hildebrandtii) and compared them to the brains of contemporary species to find out more about the behaviour of the extinct birds. Species related to elephant birds that are alive today, such as emus and ostriches, are active during the day, but features of elephant bird brains did not fit that pattern. Digital models confirmed that the optic areas of the extinct birds were significantly reduced and that the olfactory bulbs were enlarged. What does this tell us about the behaviours of these birds? A contemporary bird with reduced optic lobes is the kiwi, which has evolved hypersensitive hearing, smell and touch, and doesn’t rely on its lacking vision- it is flightless and night-active. Through the neurological similarities, researchers now assume that elephant birds also were mostly active at night. In A. maximus’, the larger of the two species, olfactory bulbs are somewhat bigger than in A. hildebrandtii, and from observations in contemporary birds the researchers concluded that A. maximus likely lived in a forested environment and A. hildebrandtii in an open grassland.

Will the next Jurassic World movie pick up on this new discovery and add huge, blind, nocturnal grazing birds roaming the forests and grasslands to its cast of prehistoric creatures? Let’s hope so.

Historic climate change lawsuit proceeds

21 plaintiffs, aged between 11 and 22, are bringing a lawsuit against the US Government that is the first of its kinds. They allege that the US government has violated their constitutional rights to life, liberty and property by failing to combat climate change. The plaintiffs hope that they can compel the US government to put policies in place that will reduce greenhouse gas emission and the use of fossil fuels.

lawsuitSince the suit was filed in 2015, the Obama and Trump administrations have asked courts to dismiss it, questioning its merit. The suit will now proceed in the 9th district court in Oregon. Its path ahead remains unclear, as the Supreme Court left it to the Federal Appeals Court to consider the government’s arguments before the trial begins in Oregon, while the youths’ lawyers are pushing for the hearing to begin in the next weeks.

Written by Maria Rappaport

Top Science News

For frack’s sake

Seven years after it was banned in the UK, fracking has begun again. Cuadrilla, an energy company, has resumed fracking at a well in Lancashire. The previous ban was due to the operations causing ‘minor earthquakes’. However, only a few days after Cuadrilla resumed activities, seismic events ranging from 0.4 to 1.1 magnitude have occurred.  Tremors of 0.8 magnitude caused work to be suspended on Friday and Saturday, with an event of 1.1. magnitude on Monday again pausing operations, as a tremor above 0.5 requires fracking to be stopped while tests are carried out.

CuadrillaThis news may be unsurprising to the many people who have protested against fracking, a controversial procedure due to the possibility of triggering seismic activity and the non-renewable nature of the energy. Earlier this month, the prison sentences of two green activists who had protested against fracking were quashed after the court of appeal ruled they were ‘excessive’. Energy sources such as coal, gas and oil exacerbate climate change and critics argue that the opening of new power plants or fracking sites indicates a lack of commitment on the government’s part to the Paris Agreement, the goal to limit the increase in global temperature to 1.5°C in order to minimise the effects of climate change.

It is unclear what will happen if seismic events continue to occur at the fracking sites in Lancashire, but it is certain that if we continue to consume and rely on fossil fuels, we will have bigger problems than 1.1 magnitude tremors.

Lavender fields forever

Do you like the smell of lavender? Maybe you have a scented candle which calms you down, or a bottle of essential oil to help you sleep. Thanks to a new study from Kagoshima University, Japan, scientific evidence is growing to suggest that the purple flower’s properties are as powerful as aromatherapy lovers have been reporting for years.

lavenderPlants and other natural products may contain a plethora of active ingredients, each contributing to its purported effects. Extracting, identifying and purifying these individual chemical components are just some of the challenges of studying the effects of natural species.

In their study, Kashiwadani and co-workers tested linalool, an alcohol from the lavender extract which has been reported to have anxiolytic effects (meaning to reduce anxiety). Mice were exposed to linalool vapour, and subsequently showed an increase in exploration of the test chamber compared to mice that had not been exposed to linalool. They also noted that this occurred without motor impairment as seen when using another anti-anxiety class of drugs, the benzodiazepines (e.g. Valium).

While the results from this study seem to support anecdotal evidence about the relaxation properties of lavender, it is worth noting that studies in mice often cannot be replicated in human patients. As mentioned previously, linalool is only one component of lavender, and until further studies have been conducted to determine the effects of the remaining compounds, lavender will be seen more in candles and bath products than in anti-anxiety drugs.

Now you see me…

Hurricane Walaka has caused a Hawaiian island to be wiped off the map. Scientists have confirmed that East Island, an 11-acre island atop a coral reef, has disappeared.

HawaiianIslandAlthough small, the island hosted a US Coast Guard Radar until 1952, and is part of a protected marine area called the French Frigate Shoals. It was home to the critically endangered Hawaiian monk seal, of which there are only 1,400 remaining in the wild, green sea turtles and other wildlife. Small, sandy islands like East Island are highly at risk due to rising sea levels associated with climate change.

The hurricane was categorized as Category 5 with winds over 157 mph. Warmer weather as well as warmer seas can affect the severity of storms, as well as their frequency. Powerful weather events like these can have a huge impact on vulnerable shores, but it remains to be seen how the wildlife that rely on the French Frigate Shoals cope with the loss of East Island.

Written by Isobel Tibbetts

Top Science News

Promising the moon

In a novel approach to doing away with streetlights, Chengdu, a city in China, has announced plans to launch an artificial moon to illuminate the city at night by 2020.

MoonAccording to the People’s Daily, the “illumination satellite” will “complement the moon at night”, at eight times the brightness of the real moon, lighting up an area of 10 x 80 km.

Wu Chunfeng, Chairman of Chengdu Aerospace Science and Technology Microelectronics System Research Institute made the announcement at a national mass innovation and entrepreneurship event held in Chengdu. He commented that the testing of the illumination satellite started years ago, but now the technology has finally matured enough to allow for launch.

The idea has been credited to a French artist who imagined hanging a necklace of mirrors above the earth to reflect sunshine through the streets. But perhaps few at the time thought that such an idea could become a reality.

Concerns have been raised regarding the reflected light from space, which could have undesirable effects on the daily routine of some animals. However, Kang Weimin, Director of the Institute of Optics, School of Aerospace, Harbin Institute of Technology, assured critics that the light of the satellite is similar to a dusk-like glow, so it should not affect the regular routines of animals.

Better the devil you know?

Although most people accept that smoking isn’t exactly a healthy habit, much research has been done to document the addictive effect of nicotine and the harmful effects of smoking are largely understood. However, less research has been done on vaping and currently, it is believed to be a safer alternative.

New research by Duke University Medical Center, published in the journal of Nicotine & Tobacco Research, has shown that what has previously been considered innocuous – flavourings added to e-liquids – could actually have considerate health consequences.

smokeChemical additives, used to make flavourings, react with compounds already present in the e-liquid creating new compounds that could trigger irritation and inflammation when inhaled. What is particularly concerning about these findings is that these reactions make new chemicals that haven’t been disclosed or thoroughly researched.

Flavourings such as cinnamon, vanilla and cherry react with solvents in the e-liquid to created acetals. According to Dr Sven-Eric Jordt, an Associate Professor of Anesthesiology, Pharmacology and Cancer Biology at Duke University Medical Center manufacturers of e-liquids have not widely documented or disclosed the presence of these acetals in the inhaled vapour.

Jordt said: “These individual ingredients are combining to form more complex chemicals that are not disclosed to the user. When inhaled, these compounds will persist in the body for some time, activating irritant pathways. In time, this mild irritation could cause an inflammatory response.”

The researchers found that when flavour additives are mixed with the e-liquid solvents around 40% of the additives are converted into acetals. And additional testing showed that 80% of these acetals were transferred into the vapour for inhalation.

The acetals were found to trigger receptors in the body involved in lung irritation, the same receptors the research demonstrated that maintain irritation and inflammation in people suffering from asthma.

Dr Hanno Erythropel, a Postdoctoral Associate in chemical and environmental engineering at Yale and a co-author of the study, said: “Individuals who use e-cigarettes frequently should know they are exposing themselves to these chemicals and that the long-term effects of these chemicals on the airways are unknown.”

Could having a daily bath help to combat depression?

Research written about this week by NewScientist has suggested that taking biweekly baths could be enough to improve the mood of those with depression.

bathA small study conducted at the University of Freiburg in Germany, as reported by New Scientist, has found that “afternoon baths just twice a week produce a moderate but persistent lift to mood.”

Currently, physical exercise is recommended to those with mild or moderate depression, but the benefit of taking a hot bath produced a similar benefit.

It has been theorised that the hot bath helps because it restores normal circadian rhythms to individuals, something that is often disturbed in those with depression. Improvements to circadian rhythms could also lead to a better night’s sleep.

A circadian rhythm is a cycle lasting around 24 hours, which is involved in body processes of all living things. The cycles can be altered by external cues such as temperature and light but are originally generated by internal mechanisms within the organism, which can become imbalanced.

An additional explanation for the results is that the hot bath causes more serotonin to be released in the body, a brain signalling molecule shown to regulate mood.

Written by Angharad Kolator Baldwin