Health: quotes, facts and reflections - Page 7

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DriveHealth

Everyday movement outside formal exercise, such as standing, walking, carrying and fidgeting, can burn hundreds of calories a day. The amount varies greatly between people and between days.

Scientists call this non-exercise activity thermogenesis, or NEAT: thermogenesis means the body's burning of energy as heat, and NEAT covers everything except sleeping, eating and deliberate exercise. In a 1999 study, James Levine and colleagues at the Mayo Clinic overfed 16 volunteers by 1,000 calories a day for eight weeks. Fat gain varied tenfold between them. The best predictor of who stayed lean was how much their everyday movement rose without their noticing: in some it fell slightly, in others it burned almost 700 extra calories a day. Because it is invisible, NEAT is easy to overlook, yet small movements across a whole day add up to a real share of energy use.

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StillnessHealth

In a 2022 study of adults aged 51 to 75, those who could not stand on one leg for ten seconds had an 84% higher risk of dying over about seven years than those who could, even after allowing for age, sex, weight and existing illness.

The study, published in the British Journal of Sports Medicine, followed 1,702 people in Brazil from 2009 to 2020. About one in five could not complete the test, which was done barefoot, with the free foot resting on the back of the other leg and arms at the sides, in up to three tries. Over the follow-up, 17.5% of those who failed died, against 4.6% of those who passed. Balance draws on leg strength, the inner ear, vision and the brain's coordination of all three, so failing can reveal several problems at once. The study shows an association, not proof that balance training extends life, but the test is quick, free and easy to add to check-ups.

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StillnessHealth

Morning light is one of the main signals that sets the body's internal 24-hour clock, known as the circadian clock. Bright outdoor daylight is usually a far stronger signal than ordinary indoor lighting.

Special light-sensing cells in the retina, separate from the ones we use to see shapes and colours, report light levels to the suprachiasmatic nucleus, a tiny area just above the point where the optic nerves cross, which acts as the body's master clock. It sets the timing of many daily rhythms, including the release of melatonin, the hormone that helps bring on sleep. Measured in lux, the unit of brightness, outdoor daylight ranges from a few thousand on a dull day to about 100,000 in full sun, while indoor lighting is often only a few hundred. Light early in the day tends to shift the clock earlier and light late in the evening shifts it later; how much depends on timing, brightness, duration and a person's existing rhythm.

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StillnessHealth

Sleeping too little in the days around a vaccination can weaken the immune response to it. In controlled studies, people whose sleep was cut short made fewer antibodies, the proteins that recognise a germ, than people who slept normally.

In a 2002 study, young men allowed only four hours' sleep a night for six nights around a flu jab had about half the antibody level of well-rested men ten days later. In another, people who stayed awake the night after a hepatitis A jab had about half the antibody level four weeks later of those who slept. A 2012 study of hepatitis B vaccination found that people who slept under six hours a night were less likely to be protected at the end of the course. A 2023 review of such studies confirmed the link, most clearly in men. Sleep seems to help the immune system turn a first encounter with a vaccine into lasting memory.

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DriveHealth

Muscles and stamina grow stronger mainly in the recovery after exercise, not during the workout itself: training is the signal, and rest, food and sleep give the body time to rebuild a little stronger.

Coaches describe this with a simplified model called supercompensation. A hard session briefly lowers the body's capacity; during recovery it not only returns to its old level but for a while rises above it, and ideally the next session comes at that point. Behind the gain are several processes: new protein built into muscle fibres, a nervous system that learns to use muscles more efficiently, and refilled fuel stores. Tiny muscle damage can occur but is not needed for every useful change. Too little rest between hard sessions can leave people tired and weaker rather than fitter. Sleep helps recovery, but adaptation goes on throughout the recovery period, not only at night.

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WonderCulture

The haenyeo of Jeju, an island off South Korea's southern coast, are women who dive without breathing equipment, holding their breath for one to three minutes to gather abalone, sea urchins, octopus and seaweed from as deep as 20 metres.

Haenyeo means 'sea women' in Korean. Girls traditionally learned the work from older divers in their village, and the women run local diving associations that set rules on when and what may be harvested and look after one another's safety. UNESCO recognised this way of caring for the sea when it added the culture of Jeju haenyeo to its Intangible Cultural Heritage list in 2016. Their numbers have fallen sharply, from 23,081 in 1965 to 14,143 by 1970 and a few thousand today. Most are now over 60, and some of the oldest, past 80, still dive.

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WonderNature

Common vampire bats form enduring social bonds and may regurgitate blood meals to hungry roost-mates, including non-relatives who have shared before.

A vampire bat that fails to feed can starve within about two to three nights, so a shared meal can be the difference between life and death. The biologist Gerald Wilkinson described the sharing in detail in 1984, from wild bats in Costa Rica, and showed that bats tend to feed those that have fed them before, a rare mammal example of reciprocal help between non-relatives. Later studies led by Gerald Carter found that new partnerships grow step by step, starting with grooming before any blood is shared. In a 2019 study, bats that had formed bonds while housed together in captivity kept many of those bonds after release into the wild, where they were tracked with tiny proximity sensors.

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WonderBiology

Cut certain planarian flatworms into pieces, and each small fragment can regrow into a whole worm within days to weeks, complete with a head and tail at the right ends.

Laboratory work focuses mostly on Schmidtea mediterranea and species of Dugesia. As early as 1898 the biologist Thomas Hunt Morgan found that a piece as small as 1/279 of a worm could regrow a whole animal; later estimates put the smallest working fragment at around 10,000 cells. The new tissue comes from neoblasts, adult stem cells spread throughout the body. In 2011 Peter Reddien's laboratory showed that a single transplanted neoblast could rebuild the tissues of a worm whose own stem cells had been destroyed by radiation. Chemical signals between cells, including the Wnt pathway that humans also have, tell each wound whether to grow a head or a tail. Planarians are now a leading model for research into how tissues might be made to repair themselves.

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WonderArchaeology

Dental calculus, the hard tartar that builds up on teeth, can trap DNA, proteins, microbes and tiny food remains for thousands of years, giving archaeologists evidence of ancient diets and health.

Plaque hardens into calculus while a person is alive, sealing in traces of whatever passes through the mouth, and it survives in the ground far better than most soft remains. In 2017 a team studying DNA in the calculus of Neanderthals from El Sidrón cave in Spain found, in a young individual with a painful dental abscess, traces of poplar, a natural source of salicylic acid, the painkiller related to aspirin, and of Penicillium mould. The researchers suggested he may have been treating himself, though that remains a hypothesis. In 2014 a team led by Christina Warinner identified a milk protein preserved in calculus from ancient teeth, direct evidence of who drank milk as dairying spread through prehistoric populations.

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DriveHealth

Alice Ball, a 23-year-old chemist in Hawaii, found in 1915 how to turn chaulmoogra oil, a traditional remedy, into an injectable medicine for leprosy, also called Hansen's disease. Her method was the most effective treatment until the 1940s.

Oil from the seeds of the chaulmoogra tree had long been used against leprosy in India and elsewhere in Asia, but it was hard to take: swallowed, it caused nausea, and injected, it formed painful blisters under the skin. Ball, the first woman and first Black American to earn a master's degree at the College of Hawaii, took up the problem at the request of the surgeon Harry Hollmann. She turned the oil's fatty acids into ethyl esters, a form that could be injected and absorbed by the body. She died in December 1916, aged 24, before she could publish. The college president, Arthur Dean, carried on the work without crediting her; Hollmann later published an account naming it the 'Ball method'. Dapsone and related drugs replaced it in the 1940s.

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DriveBiography

Filipino paediatrician Fe del Mundo opened the Philippines' first children's hospital in Quezon City in 1957, paying for it by selling her house and taking out a large loan. She also took child healthcare out to the villages, designing a bamboo incubator for places without electricity.

Born in Manila in 1911, del Mundo qualified as a doctor at the University of the Philippines in 1933 and trained further in children's medicine at Harvard Medical School and Boston Children's Hospital. She came home in 1941, just before the Japanese occupation, and cared for children held in the Santo Tomas internment camp, where she became known as “the Angel of Santo Tomas”. Her Children's Medical Center opened in 1957. She sent teams into the countryside to teach breastfeeding and child care, pressed for village midwives to be brought into the health service, and wrote a Textbook of Pediatrics long used in Philippine medical schools. In 1980 she became the first woman named a National Scientist of the Philippines. She died in 2011, aged 99.

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DriveBiography

American cancer doctor Jane C. Wright tested chemotherapy drugs on tumour tissue grown in the laboratory and compared the results with how patients responded. Her work helped move chemotherapy from trial and error towards a more systematic science.

Born in New York in 1919, Wright joined her father, the surgeon Louis T. Wright, at Harlem Hospital's Cancer Research Foundation in 1949. Instead of relying on laboratory mice, they grew samples of patients' tumours and exposed them to candidate drugs, then checked whether the laboratory results matched what happened in the clinic. In 1951 she reported that the drug methotrexate could shrink some breast and skin cancers; it is still widely used. She also devised a way to deliver strong drugs through a catheter, a thin tube, to tumours deep in organs such as the liver and spleen, without surgery. In 1964 she was the only woman among the seven doctors who founded the American Society of Clinical Oncology, and in 1967 she became associate dean at New York Medical College. She died in 2013.

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DriveBiography

In 1935 American chemist Percy Julian and his colleague Josef Pikl became the first to make the glaucoma drug physostigmine from simple chemicals. Julian later found ways to extract sterols, the raw material for many hormones, from soybeans on a factory scale, making drugs such as progesterone and cortisone far cheaper.

Physostigmine came from the Calabar bean of West Africa and was scarce. Julian's synthesis at DePauw University in Indiana also showed that a rival synthesis by the eminent British chemist Robert Robinson had gone wrong. Despite this, DePauw refused him a professorship because he was Black, and in 1936 he moved to industry as director of research at the Glidden paint company in Chicago. There, water once leaked into a tank of purified soybean oil and turned it into a solid mass. Julian recognised that it was rich in sterols, plant compounds with the same basic structure as human hormones, and turned the accident into a factory process. It made progesterone and later cortisone much cheaper. Julian held more than 130 patents, and in 1973 he became the first African-American chemist elected to the US National Academy of Sciences.

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DriveBiography

American chemist Gertrude Elion shared the 1988 Nobel Prize in Physiology or Medicine with George Hitchings and James Black. Elion and Hitchings designed drugs by studying how diseased cells and germs differ from healthy ones, instead of relying on trial and error.

Elion joined the drug company Burroughs Wellcome in New York State in 1944 as Hitchings's assistant. Their team built molecules that resemble the natural building blocks of DNA closely enough to jam the machinery of cancer cells, microbes or immune cells. The work produced 6-mercaptopurine for childhood leukaemia, azathioprine to stop the body rejecting transplanted organs, allopurinol for gout and acyclovir for herpes infections, and researchers trained in her methods later developed AZT, the first drug widely used against AIDS. Elion never finished a doctorate: after years of evening study she was told she would have to give up her job to continue full time, and she chose to keep working. Harvard and many other universities later gave her honorary degrees.

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WonderScience

Mass spectrometry reveals what a sample is made of by weighing its molecules. It gives them an electric charge, sorts them by mass and counts them, and the resulting pattern can identify drugs, pollutants, isotopes and proteins.

An ion source gives atoms or molecules an electric charge, turning them into ions. An analyser sorts them by their mass-to-charge ratio, for example by how far a magnet bends them or how long they take to fly down a tube, and a detector counts what arrives. J. J. Thomson built an early version in 1912–13 and found that neon atoms come in two different masses, the first sign of isotopes in a stable element. Francis Aston developed it into the mass spectrograph in 1919 and won the 1922 Nobel Prize in Chemistry. Gentler ways of charging molecules, developed in the 1980s, let the method weigh whole proteins and earned John Fenn and Koichi Tanaka a share of the 2002 Nobel Prize in Chemistry. Today it is used in doping tests and newborn screening.

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DriveHealth

Japanese skier and climber Yuichiro Miura reached the summit of Everest three times after turning 70: in 2003, in 2008 at 75, and on 23 May 2013, aged 80 years and 223 days. That last climb, after four operations for an irregular heartbeat, made him the oldest person on record to stand on top.

Miura first became famous in 1970, when he skied nearly 2,000 vertical metres down Everest from the South Col, the high saddle below the summit, using a parachute to slow himself. He fell for about 400 metres and stopped not far from a deep crevasse. A film of the descent, The Man Who Skied Down Everest, won the Academy Award for Best Documentary Feature, the first sports film to do so. From 2008 onwards he had four operations for arrhythmia, an irregular heartbeat. After reaching the top at 80 he could not finish the descent on foot and was flown off the mountain by helicopter from about 6,500 metres, which Guinness rules allow for a summit record.

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DriveHealth

Fauja Singh took up running in his eighties, after losing his wife and then a son. He ran his first marathon in London in 2000, at 89, and on 16 October 2011 finished the Toronto Waterfront Marathon in 8 hours 11 minutes, aged 100 by the birth date in his British passport.

Singh was a farmer from Punjab, in northern India; by family accounts he could not walk until he was five. He moved to England in the 1990s and lived with one of his sons in Ilford, east London. Guinness World Records never listed his Toronto run, because he had no birth certificate and a passport alone could not prove his age. He completed about nine marathons in all, and his last race was a 10-kilometre run in Hong Kong in 2013. He died in July 2025, aged 114 by his passport, after being struck by a vehicle in his home village of Beas Pind.

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DriveHistory

In 1967 Kathrine Switzer became the first woman to run the Boston Marathon with an official race number, having entered as 'K.V. Switzer'. A few miles in, official Jock Semple grabbed her and tried to tear off her bib, 261; her boyfriend shoved him aside, and she finished.

Boston did not accept women entrants in 1967; Bobbi Gibb had run the year before without a number, slipping in from the bushes near the start. Photographs of Semple lunging at Switzer went round the world. Her boyfriend, Tom Miller, was a hammer thrower. Afterwards the Amateur Athletic Union barred women from all races with men, until Boston officially admitted women in 1972. Switzer finished third that year, and Semple presented her trophy; the two later became friends. In 2017, fifty years after her first run, she ran Boston again at 70 wearing 261, and the organisers retired the number in her honour.

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DriveHistory

Barbara Hillary, a retired New York nurse who had survived cancer twice, skied the final stretch to the North Pole in 2007 at 75, and reached the South Pole in 2011 at 79, the first African-American woman on record to stand at both.

Hillary spent 55 years as a nurse before turning to exploration. In her twenties she survived breast cancer, and around 1998 she was treated for lung cancer with surgery that left her breathing capacity reduced by about a quarter. She learned to cross-country ski specifically for the Arctic trip and raised more than $25,000 to fund it. After reaching both poles, she became a public speaker on climate change and ageing. She died in 2019, and in 2020 she was inducted into the National Women's Hall of Fame.

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DriveHealth

In 1952 the American anaesthetist Virginia Apgar devised the Apgar score, a quick way to rate a newborn's condition right after birth. Given at one and five minutes by checking colour, heart rate, reflexes, muscle tone and breathing, it became standard in delivery rooms worldwide.

Apgar trained as a surgeon at Columbia University in the 1930s, one of very few women to do so, but the head of surgery, Allen Whipple, steered her towards anaesthesia, then a young specialty. Working at births, she saw that no one systematically checked a newborn's condition. Her score rates each of five signs 0, 1 or 2, for a total of 0 to 10; most healthy babies score 7 or more, while a low score tells staff that a baby needs help at once. In 1962 colleagues turned her name into a memory aid: Appearance, Pulse, Grimace, Activity, Respiration.

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DriveHealth

In 1960, in her first month at the US Food and Drug Administration, Frances Oldham Kelsey was asked to approve the sedative thalidomide. She found the safety data thin and held out for more than a year despite company pressure. The drug, soon linked to severe birth defects, was never sold in the US as a sedative.

Kelsey was a Canadian-born pharmacologist and doctor; in 1938 she earned the University of Chicago's first PhD in pharmacology. At the FDA she was one of only seven full-time physicians reviewing new drugs. The maker, Richardson-Merrell, pressed her repeatedly, but she kept asking for more evidence. By late 1961 doctors in Germany and Australia had linked thalidomide to severe birth defects, and in March 1962 the company withdrew its application. Even so, experimental tablets had already been given to thousands of American patients. In August 1962 President Kennedy gave Kelsey the President's Award for Distinguished Federal Civilian Service, only the second woman to receive it, and that October Congress passed the Kefauver-Harris Amendment, tightening US drug law. Decades later, in 1998, the FDA approved thalidomide under strict controls to treat a painful complication of leprosy.

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DriveMind

Brazilian psychiatrist Nise da Silveira refused to treat her patients in Rio de Janeiro with lobotomy or electroshock. From 1946 she gave them studios for painting and modelling instead, and their work became the core of the Museum of Images of the Unconscious, founded in 1952.

Da Silveira qualified in medicine in Bahia in 1926, the only woman among 157 graduates. At a public psychiatric hospital in Rio she ran the occupational therapy section, where patients were treated through practical and creative activities. She saw painting not as a pastime but as a way to understand patients who could not easily put their experiences into words. In 1956 she opened Casa das Palmeiras, an outpatient centre where former patients could keep making art as they adjusted to life outside hospital. She corresponded with Carl Jung and led Rio's C. G. Jung Study Group until 1968. In 2022 Brazil entered her name in its official Book of Heroes and Heroines of the Homeland.

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DriveHistory

Alice Coachman grew up in segregated Georgia, shut out of whites-only sports grounds, and trained barefoot on dirt roads, jumping over homemade bars of rope and sticks. At the 1948 London Olympics she won the high jump, the first Black woman to win an Olympic gold medal.

Her winning jump of 1.68 metres, cleared at the first attempt, set an Olympic record. Britain's Dorothy Tyler matched the height but needed two tries, so the gold went to Coachman, and King George VI presented her medal. She was the only American woman to win an athletics gold at those Games. Her best years had fallen in wartime, when the 1940 and 1944 Olympics were cancelled, yet she won the national high jump title of the Amateur Athletic Union ten years running, from 1939 to 1948. In 1952 Coca-Cola signed her as a spokesperson, making her the first African-American woman to endorse an international product.

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StillnessHistory

Many people in pre-industrial Europe slept in two stretches, a 'first sleep' and a 'second sleep', with an hour or more awake in between. Historian A. Roger Ekirch found more than 500 references to the pattern, though how widespread it was is still debated.

Ekirch found the references in diaries, court records, medical books and literature: people woke after a first sleep to pray, talk, work or simply rest, then went back to bed. He argues that artificial lighting and changing daily routines pushed the pattern out. In 1992 the psychiatrist Thomas Wehr kept volunteers in 14 hours of darkness each night for a month; they settled into two blocks of about four hours' sleep with a wakeful gap between. But a 2015 study of three societies without electricity, in Tanzania, Namibia and Bolivia, found that people there slept in one stretch, a finding Ekirch disputes.

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