Health: quotes, facts and reflections - Page 8

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StillnessMind

Older adults who took a weekly 15-minute walk looking out for things that filled them with awe felt more joy and less daily distress over eight weeks, a 2020 study of 60 people found. In the selfies they took on the walks, they gradually gave themselves less of the frame.

Awe is the feeling of standing before something vast that you cannot take in at once, such as a mountain view or a sky full of stars. Neuroscientist Virginia Sturm and colleagues at the University of California, San Francisco, randomly divided healthy older volunteers into two groups: one was asked to seek out awe on its walks, the other simply walked. Both took photos of themselves on every walk. Over time the awe group's selfies showed more scenery and less of the walker, and their smiles grew broader. Scores for anxiety and depression did not change in either group, so the study points to a small daily lift in mood, not a treatment.

Awe walk studyRead card

StillnessMind

Seeing or hearing birds is linked to a better mood that lasts for hours, according to a 2022 smartphone study of 1,292 people. Participants who noticed birds at one check-in also rated their mental wellbeing higher at the next one, hours later.

The study used Urban Mind, an app developed at King's College London that prompts people several times a day to say what they can see and hear at that moment and how they feel. Asking in the moment avoids the distortions of remembering one's mood later. Between April 2018 and October 2021, the 1,292 participants answered 26,856 of these prompts. The link with birdlife showed up both in healthy people and in those with a diagnosis of depression, the most common mental illness in the world. Because the study only observed people rather than testing an intervention, it cannot prove that the birds caused the lift: places with birds may be pleasanter in other ways too.

Urban Mind studyRead card

StillnessMind

Walking helps people come up with new ideas: in Stanford experiments published in 2014, participants produced on average about 60 per cent more creative ideas while walking than while sitting. The gain was clearest on tasks with many possible answers, such as finding unusual uses for an everyday object.

Psychologists Marily Oppezzo and Daniel Schwartz ran four experiments with 176 people. Their main test asked for as many uses as possible for an everyday object, a measure of 'divergent thinking': the kind that produces many options rather than one right answer. Walking raised the scores of 81 per cent of participants, whether they walked outdoors or on a treadmill facing a blank wall, so the scenery was not the explanation. The boost even lingered for a while after people sat down again. Walking helped much less with puzzles that have a single correct answer, which psychologists call convergent thinking: only 23 per cent improved on those.

Oppezzo & Schwartz, 2014Read card

StillnessMind

Silence between pieces of music can relax the body more than the music itself. In a 2006 study of 24 people, fast music raised heart rate, blood pressure and breathing; during a two-minute pause all three fell, even below the levels measured before the music began.

Physician Luciano Bernardi of the University of Pavia in Italy, with Cesare Porta and Peter Sleight, tested 12 practising musicians and 12 people of the same age without musical training. Each listened to six styles in random order, including rap, techno, Indian raga and classical music, with a two-minute pause inserted at a random point. Tempo mattered more than style: faster music and simpler rhythms were the most stimulating, while slow or meditative music had a calming effect. The musicians' breathing followed the tempo more closely than the others'. The authors suggested that alternating music and pauses might help with stress, but a single small laboratory study is only a starting point.

Bernardi study, 2006Read card

StillnessCulture

Inemuri, often translated as 'sleeping while present', is the Japanese custom of dozing in a meeting or other social or work setting while still counting as part of it. It is not simply any sleep in public: the sleeper is expected to stay ready to rejoin the situation.

The word is written 居眠り, from 'i', to be present, and 'nemuri', sleep. Brigitte Steger, a Cambridge scholar of Japanese society who has written widely about sleep in Japan, describes it as governed by unwritten rules. The higher someone's status, the more acceptable it is: a senior manager or a member of parliament nodding off in a long session can even be read as a sign of dedication, of someone who has worked to exhaustion, while a junior employee has far less licence. The sleeper should keep a proper posture and stay socially 'present', ready to respond if addressed. It is common on crowded commuter trains, but it is a tolerated custom, not an official workplace virtue.

InemuriRead card

StillnessMind

Forest kindergartens are early-years programmes, usually for children aged three to six, that use woodland or other natural settings as the main classroom. The children often spend most of the day outside, in almost any weather.

The idea is usually traced to Ella Flatau in Denmark, who in the early 1950s began spending her days with children in the woods near her home; neighbours' interest turned it into a regular kindergarten. Germany had informal nature kindergartens from 1968, but it officially recognised forest kindergartens as a form of daycare only in 1993, which opened the way to state funding. Their number grew from about 450 in 2005 to more than 1,500 by 2017. The model has since spread to Sweden, the UK, the US and beyond, sometimes under the name 'forest school'. Most keep a hut or shelter for the worst weather, but the day is built around outdoor play, with adults supporting it rather than directing it.

Forest kindergartenRead card

WonderHistory

In the autumn of 1726, Mary Toft of Godalming, in Surrey, appeared to give birth to rabbit after rabbit, and eminent surgeons, including one who served the king, vouched for the miracle. Taken to London and watched closely, she confessed to the hoax within weeks.

Toft, a young working woman, had recently lost a pregnancy. A local man-midwife, John Howard, spread word of the births, and in mid-November Nathaniel St André, surgeon-anatomist to King George I, arrived and declared them genuine. Another royal surgeon, Cyriacus Ahlers, came on 20 November and grew suspicious when he found cut marks on the animal remains and straw and grain in their droppings. In London, under constant watch and threatened with a painful operation, Toft confessed on 7 December that she had placed the animal parts inside herself. She was held at Tothill Fields Bridewell and released in April 1727, as no one could decide what to charge her with. William Hogarth mocked the doctors in his print 'Cunicularii'.

The Toft affairRead card

DriveHealth

Caring for myself is not self-indulgence, it is self-preservation, and that is an act of political warfare.

Audre Lorde, the American poet who called herself 'Black, lesbian, mother, warrior, poet', was treated for breast cancer in 1978, and in 1984 learned that the cancer had spread to her liver. A Burst of Light (1988) collects essays and the journal she kept in those years, and the sentence comes from its closing section. Throughout the book she ties care for her own body to the pressures placed on Black women, lesbians and other marginalised people, so 'self-preservation' is openly political rather than a word for pampering or consumer wellness. The book won an American Book Award; she died in 1992.

Audre Lorde, A Burst of Light (1988)Read card

StillnessHealth

Everyone who is born holds dual citizenship, in the kingdom of the well and in the kingdom of the sick.

Sontag wrote the book while being treated for advanced breast cancer, and kept herself entirely out of it: no diary, no scene at the hospital. Her target was the language around illness: the idea that tuberculosis belonged to the passionate and cancer to the repressed, and that a diagnosis says something about the person who received it. Metaphors like that, she argued, add a second illness on top of the first, and this one is made of shame. The sentence opens the book, and in 1989 she applied the same argument to AIDS in AIDS and Its Metaphors.

Susan Sontag, Illness as Metaphor (1978)Read card

WonderHealth

Bayer credits its chemist Felix Hoffmann with making aspirin's active ingredient, acetylsalicylic acid, in a stable form in 1897, but that account is disputed. In 1949 his senior colleague Arthur Eichengrün wrote that he had directed the project and given Hoffmann the task. Historian Walter Sneader supported Eichengrün's claim in 1999; Bayer and other historians do not accept it.

Eichengrün was Jewish and was persecuted under the Nazi regime; in 1944, aged 76, he was imprisoned at Theresienstadt, where he typed a letter worded much like the paper he published in 1949. The account crediting Hoffmann had first appeared in 1934, as a footnote in a history of chemical engineering, and Sneader argued that in the Nazi years Eichengrün was in no position to rebut it in public. Bayer registered the name Aspirin in 1899. The drug went on to become one of the best-selling medicines in history and helped make Bayer a major pharmaceutical company.

Arthur Eichengrün / Felix Hoffmann, Bayer, 1897 (dispute surfaced 1949, re-examined 1999)Read card

WonderHealth

In 1747, Royal Navy surgeon James Lind took twelve sailors with scurvy aboard HMS Salisbury, divided them into pairs and gave each pair a different remedy while keeping their basic diet and conditions similar. The pair given oranges and lemons improved most dramatically. Small and unrandomised by modern standards, the experiment is remembered as an early controlled therapeutic trial.

Scurvy, caused by a lack of vitamin C, brings bleeding gums, weakness and reopened wounds, and it killed huge numbers of sailors on long voyages; vitamin C itself was not identified until the 1930s. Lind's six pairs received cider, dilute sulphuric acid, vinegar, seawater, two oranges and a lemon, or a spicy paste with barley water. The fruit ran out after six days, but by then one of the citrus pair was fit for duty. Lind published his results in 1753, yet the Admiralty only made lemon juice a standard ration across the fleet in 1795. In the 19th century the navy switched to cheaper West Indian lime juice, which holds far less vitamin C.

James Lind, HMS Salisbury, 1747Read card

WonderHealth

The stethoscope began in 1816 with a roll of paper. French physician René Laennec, examining a young woman, thought it unsuitable to press his ear to her chest, so he rolled paper into a tube and found that heart sounds travelled through it clearly. He later made a wooden version and called the method mediate auscultation, meaning listening through an instrument.

Laennec called his method 'mediate auscultation' because the instrument stood between his ear and the patient, unlike direct auscultation, in which a doctor listened with an ear right on the chest. He soon replaced the rolled paper with a hollow wooden cylinder about 25 cm long, a shape doctors kept using for decades. The word stethoscope comes from the Greek stethos, chest, and skopein, to examine. Laennec spent years comparing the sounds he heard in living patients with what autopsies later showed, laying the foundations of a diagnostic method still used today. He died of tuberculosis in 1826, aged 45; his nephew is said to have diagnosed the disease with Laennec's own stethoscope.

René Laennec, Paris, 1816Read card

WonderHealth

In late 1951, doctoral student Eugene Aserinsky recorded the brain activity and eye movements of his eight-year-old son, Armond, during sleep. The recording showed periods of rapid eye movement and brain activity unlike the quiet sleep he expected. Aserinsky and his supervisor Nathaniel Kleitman published their findings in 1953, linking this stage, now called REM (rapid eye movement) sleep, to dreaming.

Aserinsky was a doctoral student with little equipment of his own, so he first tried an old brain-wave (EEG) machine on his son Armond before using it on adult volunteers. REM stands for rapid eye movement: stretches of sleep in which the eyes dart about and brain activity resembles waking, even though the sleeper stays asleep. Aserinsky and Kleitman published the discovery in 1953 in the journal Science, and Kleitman's later student William Dement showed that REM sleep returns in cycles roughly every 90 minutes through the night. The finding turned sleep, until then seen as a single passive state, into an active subject for laboratory research.

Eugene Aserinsky & Nathaniel Kleitman, University of Chicago, 1953Read card

WonderHealth

Karl Landsteiner discovered human blood groups in 1901, explaining why some early blood transfusions ended in deadly reactions. Mixing serum and red cells from himself and his colleagues, he saw that some combinations made the cells clump. He sorted blood into groups A, B and O; others described AB soon after, and safe transfusion became possible.

Before 1901, doctors did not know that blood comes in types that can clash, so transfusions between people succeeded or failed almost by chance. Landsteiner, an Austrian doctor working in Vienna, noticed that serum from one person could make another person's red cells clump; he named the groups A, B and C, the last later renamed O. Matching donor and patient, together with new ways to store blood, made transfusion far more common by the First World War. Landsteiner received the Nobel Prize in 1930, and in 1937, with Alexander Wiener, he identified the Rhesus (Rh) factor, which matters for transfusion and pregnancy.

Karl Landsteiner, 1901 (Nobel Prize 1930)Read card

WonderHealth

The phrase "first, do no harm" appears nowhere in the Hippocratic Oath, though many people think doctors swear it. The ancient Greek oath instead promises to keep patients from harm and injustice and never to give a deadly drug, even if asked. The Latin "primum non nocere" came into use many centuries later.

Hippocrates was a physician on the Greek island of Kos in the 5th century BC, later called the father of Western medicine. The oath that carries his name may not be his own work: it is one of about sixty texts by various authors gathered in the Hippocratic Corpus. The idea behind the famous phrase does appear in another of them, the Epidemics, which tells doctors to help, or at least to do no harm. Today many medical schools use modern oaths instead, such as the World Medical Association's Declaration of Geneva, first adopted in 1948 after the crimes of Nazi doctors came to light.

Hippocratic corpus, ancient Greece (phrase's later attribution disputed)Read card

WonderHealth

The face of Resusci Anne, the CPR training mannequin Åsmund Lærdal developed around 1960, comes from L'Inconnue de la Seine, a death mask of an unidentified young woman sold widely in Europe for decades before. Stories say she was pulled from the Seine in late-19th-century Paris, but neither her identity nor the drowning story is documented.

Åsmund Lærdal was a Norwegian toy maker who worked with the anaesthetists Peter Safar and Bjørn Lind to build a lifelike mannequin for practising mouth-to-mouth rescue breathing, which had recently been shown to work. He wanted a calm, natural face and chose the mask, which he remembered from a relative's home. Casts of it had been sold in Paris since around 1900, and it became a fashionable ornament in homes and studios; Rilke and Nabokov were among the writers who wrote about it. Because a drowned face is rarely so peaceful and unmarked, many doubt the Seine story and think the model may have been alive. Resusci Anne has since been called the most-kissed face in the world.

L'Inconnue de la Seine (death mask) / Åsmund Lærdal, Resusci Anne, 1960Read card

WonderHealth

In 1944, physiologist Ancel Keys began the Minnesota Starvation Experiment with 36 conscientious objectors who volunteered to go hungry. After three months of normal eating, the men spent six months on about half their usual food while walking miles each week, losing about a quarter of their weight. The study recorded the physical and mental effects, then tested ways to refeed them.

Conscientious objectors were men who refused military service on moral or religious grounds; in the United States many did alternative public service instead, and these volunteers chose this study. The project was designed to guide famine relief in war-torn Europe. As the months passed, many became obsessed with food, reading cookbooks and planning menus, grew irritable and depressed, and lost interest in almost everything else; some effects lasted long into recovery. Keys and his colleagues published the results in 1950 as The Biology of Human Starvation. Because an experiment like it would not be allowed today, it is still cited in famine relief and in treating eating disorders.

Ancel Keys, Minnesota Starvation Experiment, 1944–1945Read card

WonderHealth

The popular target of 10,000 steps a day comes from a Japanese step counter sold in the mid-1960s as the manpo-kei, meaning '10,000-step meter'. It was a catchy goal, not a threshold set by clinical research.

In 1963, ahead of the Tokyo Olympics, Iwao Ohya, head of a large Tokyo clinic, told engineer Juri Kato of the clock and meter maker Yamasa that Japanese people were moving too little and should walk 10,000 steps a day. Two years later Kato's manpo-kei went on sale, and walking clubs soon formed in all 47 of Japan's prefectures. The figure spread abroad through marketing rather than research. A 2025 review of dozens of studies found that about 7,000 steps a day was linked with much of the benefit for the risk of death and disease, with smaller gains beyond that for most outcomes.

Manpo-kei history; modern step-count epidemiologyRead card

WonderHealth

Leptin is a hormone, made mainly by body fat, that tells the brain how much energy the body has in store. Jeffrey Friedman's team at Rockefeller University found it in 1994 by tracking down a mouse gene called ob, short for 'obese', which carries the instructions for making it.

Friedman's team spent eight years on positional cloning: narrowing down a faulty gene from its rough position on a chromosome, long before DNA sequencing made such searches easy. They named the hormone after the Greek leptos, meaning thin. A small number of people are born with a mutation that leaves them unable to make leptin; from early childhood they feel constant hunger and become severely obese, and daily leptin injections quickly curb their hunger and bring their weight down dramatically. That response confirmed the hormone's role. Most common obesity is different: leptin levels are normal or high, and the problem is that the brain responds to the signal less strongly.

Jeffrey M. Friedman, Rockefeller University, 1994Read card

WonderHealth

Mary Mallon, an Irish-born cook in New York, was the first person in the United States identified as a healthy carrier of typhoid: she spread the bacteria without ever falling ill. After outbreaks were traced to households she had cooked for, health officials held her on an island in the East River for three years, then, when she went back to cooking, for her last 23 years.

Mallon was born in 1869 in Cookstown, County Tyrone, Ireland, and emigrated to the United States at about 15. In 1907 sanitary engineer George Soper traced a string of typhoid cases to families she had worked for; Mallon, who had never felt ill, refused to believe him. She was held in a cottage on North Brother Island until 1910, then released on condition that she stop cooking. In 1915 an outbreak at a Manhattan maternity hospital was traced to a cook calling herself Mary Brown: it was Mallon. She was sent back to the island and died there in 1938. Officials identified about 400 other healthy carriers in New York during her confinement; none were held as long.

Mary Mallon ("Typhoid Mary"), New York, 1900s–1938Read card

WonderHealth

During the Dutch Hunger Winter of 1944–45, a German blockade left the western Netherlands with rations as low as 400–800 calories a day. Researchers who followed babies exposed in the womb found higher rates of obesity, diabetes and heart disease decades later, depending on when in pregnancy the famine struck. It became a leading human example of how nutrition before birth may leave chemical marks on genes.

The famine had a clear start and end, and Dutch records were good, so researchers could compare people by exactly when they were exposed in the womb. Those exposed early in pregnancy later had more heart disease and higher body weight, and those conceived at the famine's height had about twice the usual risk of schizophrenia. Exposure late in pregnancy meant smaller babies and, later, poorer control of blood sugar. A 2008 study found that people exposed around conception still had less methylation on the growth gene IGF2 six decades on; methylation is a chemical tag on DNA that can turn a gene's activity up or down without changing its code. A 2024 study linked the famine to faster biological ageing on some, but not all, measures.

Dutch Hunger Winter Families Study, ongoing since the 1990sRead card

WonderHealth

Runner's high, the calm, euphoric feeling some people get during or after long exercise, was long credited mainly to endorphins. Experiments in mice and studies in people now suggest that endocannabinoids, signalling molecules the body makes that act on the same receptors as cannabis, play an important part in easing anxiety and pain after exercise.

Endorphins are the body's own opioids, chemicals that act like morphine. A 2008 brain-scan study in runners found opioid activity rising after a two-hour run, which supported the old explanation. But endorphins in the blood barely reach the brain, and in 2015 a German team showed that blocking cannabinoid receptors in mice took away the calming and pain-relieving effects of running, while blocking opioid receptors did not. A 2021 study in people found a similar pattern: runners still felt the high when their opioid receptors were blocked, and their endocannabinoid levels rose. Many researchers now think endocannabinoids do much of the work, though opioids may also play a part.

Fuss et al., PNAS (2015) and subsequent researchRead card

WonderHealth

Two long US studies of calorie restriction in rhesus monkeys, begun in the late 1980s, disagreed about lifespan. At the University of Wisconsin, monkeys fed about 30% fewer calories lived longer than controls; at the National Institute on Aging (NIA), survival did not clearly improve. A joint analysis traced much of the gap to the controls: Wisconsin's ate freely from a sugar-rich diet, the NIA's had measured portions.

Calorie restriction means eating markedly less than usual while still getting all essential nutrients; since the 1930s it had been known to extend the lives of rats and mice. Monkeys age far more slowly, so both studies ran for decades. Besides the control diets, the two projects differed in the age at which restriction began and in the monkeys' origins, Indian or Chinese. In 2017 the two teams published a joint analysis concluding that calorie restriction does improve health and survival in rhesus monkeys. Both studies found that restricted monkeys developed age-related diseases such as diabetes and cancer less often or later. Whether the same holds for people is still unknown.

University of Wisconsin & National Institute on Aging primate studies, 1980s–2010sRead card

WonderHealth

In the 1860s, Louis Pasteur studied fermentation and the microorganisms that spoiled wine and beer. He showed that controlled heating, without boiling, could prevent unwanted microbial changes, and patented a process for preserving wine in 1865. The same principle was later applied to milk and other foods and became known, after him, as pasteurisation.

Wine was one of France's great export industries, and unpredictable spoilage was a serious economic problem, so in 1863 Emperor Napoleon III asked Pasteur to investigate. Linking spoilage to specific living microorganisms gave strong early support to what became known as germ theory: the idea that particular microbes, not spontaneous decay or 'bad air', cause fermentation, rotting and disease. Over the next two decades Pasteur applied the same reasoning to human and animal illness, developed vaccines against anthrax and rabies, and helped found modern microbiology. Pasteurisation, heating a liquid enough to kill most harmful microbes without cooking it, is still used today, usually at higher temperatures for shorter times than Pasteur's method.

Louis Pasteur, 1864–1865Read card