146 Fun Facts About Health and Wellness

The 10,000-steps-a-day target took off with a 1960s pedometer, the 'ten-thousand step meter', sold in which country?

Japan's clockmaker Yamasa sold the manpo-kei, or 'ten-thousand step meter', from 1965; the catchy number stuck, though a 2019 Harvard study of older women found the benefit levelling off near 7,500 steps.

The brain's master body clock sits directly above the crossing point of which nerves?

Optic nerves cross at the optic chiasm, and the suprachiasmatic nucleus sits just above it in the hypothalamus, so light signals from the eyes reach the clock directly and keep it in step with the day.

How many minutes of moderate-intensity activity per week does the WHO recommend for adults at minimum?

WHO's 2020 guidelines advise at least 150 minutes of moderate activity a week; they also dropped the old rule that exercise only counted in bouts of ten minutes or more, so every short walk now adds up.

WHO's 2024 study found roughly what share of adults worldwide fall short of recommended activity levels?

About 31% of adults, some 1.8 billion people, were insufficiently active in 2022, the WHO's Lancet Global Health study found; that was up from 23% in 2000 and on course for 35% by 2030.

How many hours of sleep per night does the National Sleep Foundation recommend for adults aged 18 to 64?

The National Sleep Foundation's 2015 guidance recommends 7 to 9 hours for adults aged 18 to 64; newborns are advised 14 to 17 hours and over-65s 7 to 8.

A full cycle of non-REM and REM sleep takes, on average, how long?

A full non-REM plus REM cycle lasts about 90 minutes and repeats through the night; the REM share grows with each cycle, so most dreaming falls in the hours before waking.

REM sleep is nicknamed what, since the brain acts awake while the body is paralysed?

Paradoxical sleep was Michel Jouvet's 1959 name for REM; the paralysis is a safeguard that stops sleepers acting out their dreams, and people in whom it fails can punch and kick their way through them.

Which hormone, secreted by the pineal gland at night, regulates the sleep-wake cycle?

Melatonin is the pineal hormone that rises in darkness; dermatologist Aaron Lerner isolated it in 1958 from cow pineal glands while hunting for a substance that lightened frog skin.

The word "circadian" comes from Latin words meaning what?

Circadian comes from Latin circa diem, 'about a day', coined by Franz Halberg in 1959; in 1729 Jean-Jacques de Mairan showed a mimosa kept its daily leaf rhythm in constant darkness.

For a 'coffee nap', researchers advise drinking the coffee when?

Just before dozing off: caffeine takes about 20 minutes to kick in, so it arrives as a short nap ends, and in driving-simulator tests the pair cut sleepy drivers' errors far more than caffeine alone.

Whose 1990s study found that pilots who took a 26-minute cockpit nap stayed markedly more alert?

NASA let long-haul crews take a planned 40-minute cockpit rest; they slept 26 minutes on average and stayed more alert right through descent and landing than crews who flew on without a break.

Roughly how long does a healthy adult take to clear half a dose of caffeine?

About 5 hours is typical in healthy adults, within a range of roughly 3 to 7, so half the caffeine in a 4 pm coffee is still circulating at 9 pm and a quarter of it in the small hours.

Caffeine keeps you awake by blocking receptors for which sleep-promoting molecule?

Caffeine is an adenosine receptor antagonist: adenosine builds up during waking hours and signals sleepiness, and caffeine's similar shape lets it occupy those receptors without activating them.

Health Canada advises healthy adults to consume no more than how much caffeine per day?

Health Canada's limit for healthy adults is 400 mg of caffeine a day, a level a 2017 systematic review judged safe; just three times that, swallowed at once as pure caffeine powder, can trigger seizures.

Which of these counts towards the WHO's limit on 'free sugars', alongside table sugar, honey and syrups?

Fruit juice counts towards the WHO limit of 10% of daily energy, roughly 50 grams of free sugars, but whole fruit and milk do not, because the WHO found no evidence that their sugars do harm.

The WHO's daily salt limit for adults, 5 grams, comes to roughly how much?

A teaspoon, or just under, holds the WHO's 5-gram ceiling, which equals 2 grams of sodium; the average adult worldwide eats about 11 grams of salt a day, more than double the limit.

Which vegetable does the WHO leave out of its 400 g daily fruit-and-vegetable target?

Potatoes are left out, along with other starchy tubers, because they are eaten as the meal's starch in place of bread or rice; Britain's 5 A Day slices the same 400 g into 80-gram portions.

According to the WHO, no more than what share of total energy should come from trans fat?

WHO caps trans fat at under 1% of total energy, about 2 grams a day; its 2018 REPLACE campaign set out to clear industrial trans fat from the world's food by the end of 2023 and missed the target.

From June 2018, the US banned which main industrial source of trans fat from food?

The FDA had ruled in 2015 that partially hydrogenated oils were not generally recognised as safe.

Which hormone, also called ADH, tells the kidneys to reabsorb water when the body is dehydrated?

Vasopressin, or antidiuretic hormone, is released by the posterior pituitary and makes the kidneys return water to the blood; alcohol suppresses its release, which is why drinking sends people to the toilet so often.

Drinking far too much water can dilute blood sodium into a dangerous condition called what?

Hyponatremia is dangerously low blood sodium; water intoxication from overdrinking is why US Army guidance caps fluid intake at about 1 to 1.5 litres per hour during heavy sweating.

Humans must eat which vitamin because the gene for the last enzyme needed to make it is broken?

Humans cannot make Vitamin C because the GULO gene for the final enzyme is broken; guinea pigs share the defect, which is how two Norwegian doctors stumbled on the first animal model of scurvy in 1907.

Which naval surgeon showed in 1747 that citrus fruit treats scurvy, in an early controlled clinical trial?

James Lind, aboard HMS Salisbury in 1747, gave pairs of scurvy patients cider, vitriol, vinegar, seawater, a spice paste or oranges and lemons; only the citrus pair recovered quickly.

Which vitamin is also a hormone that the body can make for itself?

Vitamin D is made in the skin under the sun's UVB rays, which for most people supplies more than diet does; darker skin makes less of it, because the pigment melanin acts like a shade.

Which vitamin, found naturally only in animal foods, is built around a single atom of cobalt?

Vitamin B12 is built around a single cobalt atom, hence its chemical name cobalamin; working out its structure by X-ray crystallography helped win Dorothy Hodgkin the 1964 Nobel Prize in Chemistry.

Flaxseed, chia and walnuts supply ALA, the plant form of which family of fats?

Omega-3 in plants comes as alpha-linolenic acid, or ALA, which the body cannot make for itself; it converts only a small share into the EPA and DHA found in oily fish, so those two are best eaten directly.

Which nutrient is defined as the part of plant food that human digestive enzymes cannot fully break down?

Dietary fibre passes through the small intestine undigested; microbes in the large intestine then ferment part of it into short-chain fatty acids, while the rest adds the bulk that keeps the bowel regular.

Which eating pattern does UNESCO list as Intangible Cultural Heritage?

The Mediterranean diet won its UNESCO listing as a way of life, not a menu: the citation covers harvesting, fishing and cooking, and calls shared meals the foundation of the region's cultural identity.

The body mass index divides a person's weight by the square of what?

Height squared sits under weight in a formula from the 1830s by Belgian astronomer Adolphe Quetelet; Ancel Keys, who named it the body mass index in 1972, judged it fit for studying populations, not for assessing individuals.

A body mass index of 30 or more puts an adult in which BMI category?

Obese begins at a BMI of 30, with overweight from 25; because the index cannot tell muscle from fat, heavily muscled athletes can land in the obese band without carrying excess fat.

Which so-called 'stress hormone' peaks in the early morning around the time of waking?

Cortisol jumps by about half in the 30 to 45 minutes after waking, a surge called the cortisol awakening response that is thought to ready the body for the day; levels then ebb to their low by evening.

Harvard cardiologist Herbert Benson based his 1975 book The Relaxation Response on studies of people doing what?

Meditating volunteers had asked Harvard to test them; Benson found their breathing, heart rate and metabolism all slowed, then showed that quietly repeating any simple word could bring on the same response.

The International Day of Yoga, first held in 2015, is timed to which seasonal turning point?

The June solstice was Narendra Modi's suggestion when he proposed the day at the UN in 2014, because it is the longest day of the year in the northern hemisphere; a record number of member states backed the resolution.

Health advice says to wash your hands for about as long as it takes to sing which song twice?

Happy Birthday sung twice lasts about 20 seconds, the scrub the NHS and CDC advise; the CDC adds that the water's temperature makes no difference, so cold works as well as warm.

The WHO's World Hand Hygiene Day, held each 5 May, is aimed chiefly at which group?

Health workers are the audience for the WHO's 'SAVE LIVES: Clean Your Hands' campaign each 5 May, because it targets infections spread during care; children were the stars of the first Global Handwashing Day, a separate October event.

A sunscreen's SPF rating compares how much sunlight it takes to make protected and bare skin do what?

Burn is the test: SPF 15 means about 15 times the dose of UV is needed to redden protected skin; it is not a timer, the FDA warns, since 15 minutes of early-afternoon sun can deliver as much as an hour at 9 am.

Chemist Franz Greiter, credited with the SPF scale, named his sunscreen brand after which Alpine peak?

Piz Buin, on the Austrian-Swiss border, is where Greiter is said to have been scorched by the sun on a 1938 climb; the Glacier Cream he launched in 1946 has been estimated at an SPF of just 2.

A sunscreen labelled "broad-spectrum" protects against which two types of radiation?

'Broad-spectrum' means protection against both UVA and UVB; the SPF number speaks mainly to UVB, so a high SPF alone says little about UVA, which penetrates deeper and drives skin ageing.

What does the science say about cracking your knuckles and arthritis?

There is no evidence of a link: a 2011 study of 215 people found knuckle-cracking made no difference to hand arthritis rates, however often or for how long they cracked.

Dr Donald Unger won which spoof award in 2009 for cracking the knuckles of only one hand for over 60 years?

An Ig Nobel Prize in medicine went to Unger, a California doctor, for his one-man trial: he cracked the knuckles of his left hand, never his right, every day for decades and wrote it up for a rheumatology journal.

What is the medical name for the wear-and-tear arthritis that erodes joint cartilage?

Osteoarthritis is the gradual breakdown of the cartilage that covers the bone ends in a joint; rheumatoid arthritis is different in kind, an attack by the body's own immune system on the joint lining.

Which Italian island's mountain villages, noted for long-lived men, became the first Blue Zone?

Sardinia's mountain province of Nuoro stood out in a 2004 study for the exceptional longevity of its men; the demographers had marked the long-lived villages on their map in blue pen, and the label stuck.

Which Greek island is counted among the five Blue Zones?

Ikaria, a Greek island in the eastern Aegean, is one of the five Blue Zones; its reputed longevity is credited to a diet of greens, beans and olive oil, daily naps and strong community ties.

The Nicoya Peninsula, a Blue Zone, belongs to which Central American country?

Costa Rica's Nicoya Peninsula stood out when a study found its elderly men dying at a rate a fifth below other Costa Ricans'; the Blue Zones team points to its calcium-rich water and a strong sense of purpose, the 'plan de vida'.

Dan Buettner brought the Blue Zones to a mass audience with a 2005 cover story in which magazine?

National Geographic ran Buettner's 'Secrets of Long Life' in November 2005 after backing his trips to Okinawa and Loma Linda; he went on to found a company, Blue Zones LLC, around the idea.

Nobel laureate Élie Metchnikoff launched probiotic theory by crediting Bulgarian peasants' long lives to which food?

Yoghurt's lactic-acid cultures, Metchnikoff argued around 1907, crowd out the gut microbes he blamed for ageing; he drank sour milk every day himself, and for a time his fermented-milk diet was widely popular.

How does the WHO define probiotics?

Live microorganisms that benefit the host is the nub of the 2001 WHO expert definition, which adds 'when administered in adequate amounts'; the microbes must be alive and shown to help, so not every fermented food qualifies.

The WHO advises at least 30 minutes a day of which activity for babies who cannot yet crawl?

Tummy time, lying awake on the front, builds the muscles a baby needs for sitting and crawling; the same 2019 WHO guidelines advise no screen time at all before age two and at most an hour a day from two to four.

During slow-wave (deep) sleep, humans secrete bursts of what?

Growth hormone comes in pulses tied to slow-wave sleep, the biggest of the day arriving soon after sleep begins; that link is one reason deep sleep is thought to help the body repair muscle and other tissue.

In quiet waking, roughly what share of the body's energy does the brain use?

The brain uses about 20% of the body's resting energy on roughly 2 percent of its weight; hard thinking barely moves the figure, because the brain's round-the-clock baseline activity dwarfs the extra cost of any task.

Deep sleep, the third stage of non-REM sleep, is dominated by which slow, high-amplitude brain waves?

Delta waves, the slowest of the classic brain rhythms at about 0.5 to 4 cycles a second, mark the deepest sleep; in 2007 sleep scientists merged the old stages 3 and 4 into this single stage, cutting non-REM sleep from four to three.

A resting heart rate above 100 beats per minute in an adult is known as what?

Tachycardia starts above the normal resting range of 60 to 100 beats a minute; a rate below 60 is bradycardia, which in trained athletes is no cause for concern, since a stronger heart pumps more blood with each beat.

Blood pressure is conventionally measured in which unit?

Millimetres of mercury (mmHg) recall the mercury column of the classic gauge; the AHA counts normal resting pressure as under 120/80, and the gap between the two numbers is the pulse pressure.

Carl Wunderlich took the readings behind the 37 °C 'normal' body temperature from which part of his patients?

The armpit: Wunderlich gathered millions of readings there from some 25,000 Leipzig patients, using a thermometer said to be a foot long that took 20 minutes to register, and published his figure in 1868.

A 2020 Stanford study of US records back to the 1860s found average body temperature has done what?

Fallen steadily, by about 0.03 °C for each decade of birth, Julie Parsonnet's team found; they suggest modern people run cooler because they carry far less chronic infection and inflammation than their ancestors did.

Michael Mosley's 2013 book The Fast Diet popularised which pattern of intermittent fasting?

The 5:2 diet means eating normally five days a week and about a quarter of the usual calories, 500 to 600, on the other two; Mosley tried it on camera for the BBC's Horizon after finding alternate-day fasting impractical.

New Orleans dentist Levi Spear Parmly is credited with inventing which bathroom staple in the 1810s?

Floss began as the waxed silk thread Parmly urged patients to run between their teeth in his 1819 guide to dental care; nobody sold it commercially until 1882, more than 60 years later.

The word 'endorphin' is a contraction of which two-word phrase?

Endorphin contracts 'endogenous morphine': once researchers saw that opiates act on receptors in the brain, they reasoned the body must make its own painkillers to fit them, and Aberdeen scientists isolated the first in the 1970s.

Long static stretching before exercise is discouraged as it can temporarily reduce what?

Long static stretches temporarily reduce strength and peak performance, a 2013 meta-analysis found, regardless of age, sex or training status, so a dynamic warm-up is recommended before exercise.

Which school's researchers created the sports drink Gatorade in 1965?

Researchers at the University of Florida led by kidney specialist Robert Cade mixed the first Gatorade in 1965 for the heat-drained Gators; after Florida won the 1967 Orange Bowl, the losing coach said, 'We didn't have Gatorade.'

Red Bull was adapted in the 1980s from Krating Daeng, an energy drink from which country?

Thailand's Krating Daeng cured Austrian marketer Dietrich Mateschitz's jet lag on a business trip, by his account; he teamed up with its creator Chaleo Yoovidhya, added fizz for Western tastes and launched Red Bull in 1987.

Blue Monday, billed as the year's most depressing day, began as a 2005 publicity stunt for which industry?

Travel: a holiday firm, Sky Travel, announced the first Blue Monday in a 2005 press release built on a formula from psychologist Cliff Arnall; critics have dismissed the equation as pseudoscience dressed up to sell holidays.

Since 2007 the EU has barred marketing foods under which buzzword unless an approved health claim backs it up?

'Superfood' has no official or legal definition, so under EU rules that took effect in July 2007 the word may appear on a product only alongside a specific health claim that is backed by evidence.

The world's first food pyramid was published in 1974 in which country?

Sweden's cooperative KF published the first food pyramid in 1974, devised by Anna-Britt Agnsäter after a 1972 push to identify cheap, nutritious basics during high food prices.

In 2011 Michelle Obama unveiled which USDA nutrition guide, ending 19 years of food pyramids?

MyPlate swapped the pyramid for a place setting split into fruit, vegetables, grains and protein; Michelle Obama's pitch was that parents have no time to measure portions but can glance at a child's plate.

In conventional medicine, the ketogenic diet is used mainly to treat what in children?

The ketogenic diet has treated childhood epilepsy since the 1920s; it faded once anticonvulsant drugs arrived, and today it is usually tried only after at least two medicines have failed.

Alcohol hand sanitiser works poorly against which stomach bug?

Norovirus lacks the outer envelope that alcohol attacks, so health agencies say only soap and water will do; against most other germs a sanitiser works best at 60 to 95% alcohol.

Noise-induced hearing loss is permanent because humans cannot regrow which inner-ear cells?

Hair cells in the cochlea turn sound into nerve signals; birds and frogs can regrow theirs, but in humans each one killed by noise is gone for good, which is why US workplaces must act from 85 decibels.

Most adults worldwide lose much of their ability to digest which sugar?

Lactose needs the enzyme lactase, which most mammals stop making after weaning; lifelong tolerance is the newcomer, a trait that evolved recently in peoples with a long history of dairy herding.

Which group of viruses causes more common colds than any other?

Rhinoviruses come in well over 100 types among more than 200 cold viruses, and that sheer variety is why no vaccine against the common cold has been made.

Which weekly campaign did ad man Sid Lerner launch in 2003 with Johns Hopkins?

Meatless Monday asks people to skip meat one day a week for their health and the planet; its name echoes the 'meatless' and 'wheatless' days of US food-saving drives in the First World War.

The Veganuary pledge to eat vegan for a month began in 2014 in which country?

The United Kingdom: Jane Land and Matthew Glover launched Veganuary from York with 3,325 sign-ups in January 2014, and by 2021 more than half a million people were taking the pledge.

Which product does the World Health Organization campaign against with a global 'no' day every 31 May?

Tobacco: the World Health Assembly first called for a one-off 'world no-smoking day' on 7 April 1988, then made World No Tobacco Day an annual fixture on 31 May to spotlight a preventable cause of death.

World Health Day marks the 1948 founding of the WHO, which has its headquarters in which city?

Geneva houses the WHO, whose constitution took force on 7 April 1948, the date kept as World Health Day; that text defines health as complete physical, mental and social well-being, not merely the absence of disease.

Which swimmer's purple cupping bruises drew worldwide attention at the 2016 Rio Olympics?

Michael Phelps's bruises came from cupping, in which a heated cup creates a vacuum that sucks the skin upward and bursts tiny blood vessels; athletes swear by it for recovery, but no benefit has been scientifically proven.

The word 'siesta' comes from a Latin phrase for which hour, counting from dawn?

Siesta comes from the Latin sexta hora, the sixth hour: Romans counted the hours from dawn, so the sixth fell at noon, the hottest part of the day and the natural time to stop and rest.

The word 'sauna' entered English from which language?

Finnish lent English the word in the 1880s; Finland has over three million saunas for 5.5 million people, and older Finns were often born in one, since it was a sterile room with hot water to hand.

Transcendental Meditation was developed by which teacher?

Maharishi Mahesh Yogi began teaching the silent-mantra technique in India in 1955 and took it abroad from 1958; The Beatles studied with him at Rishikesh in 1968 and wrote much of the White Album during the stay.

Dutch cold-exposure athlete Wim Hof is known by what nickname?

The Iceman has held Guinness records for swimming under ice and running a barefoot half marathon on snow; in a 2014 Dutch trial, volunteers trained in his methods showed a milder immune reaction to an injected toxin.

In the kombucha starter called a SCOBY, what does the 'B' stand for?

Bacteria share the 'symbiotic culture of bacteria and yeast' with yeasts that turn the tea's sugar into alcohol; the bacteria then turn that alcohol into vinegar-like acid, which is why kombucha tastes tart.

Who founded the 1979 Stress Reduction Clinic behind mindfulness-based stress reduction?

Jon Kabat-Zinn, an MIT-trained molecular biologist, opened the clinic at the University of Massachusetts Medical Center for patients in chronic pain, teaching them Buddhist meditation recast in secular, medical language.

Teenager Randy Gardner's famous 1964 sleep-deprivation record kept him awake how long?

Gardner, a 17-year-old San Diego schoolboy, stayed awake 264 hours, just over 11 days, for a science fair as Stanford's William Dement looked on; Guinness later stopped accepting attempts on the record as too dangerous.

Ghrelin, nicknamed the 'hunger hormone', is made mainly by which organ?

The stomach releases ghrelin when it is empty, so levels climb before meals and fall after eating; they also rise after dieting, one reason lost weight tends to creep back on.

Which doctor slashed deaths on an 1847 Vienna maternity ward by making colleagues wash their hands?

Ignaz Semmelweis had doctors scrub in chlorinated lime after seeing their ward, staffed straight from the autopsy room, lose far more mothers than the midwives'; deaths plunged, yet many colleagues rejected him and he died in an asylum.

In a blood pressure reading, what is the first and higher number, taken as the heart beats, called?

Systolic pressure is read at the moment the loosening cuff lets blood tap through the artery again, and diastolic when the tapping fades; under 2017 US guidelines, stage 1 hypertension starts at 130 over 80.

Psychologist Herbert Freudenberger used which word in a 1974 paper for the exhaustion of volunteers at a New York free clinic?

Burnout was what Freudenberger saw in the clinic's unpaid staff, himself included, after months of punishing hours; in 2019 the WHO listed it as an occupational phenomenon, not a medical condition.

Which exercise is named after the American who devised it in 1939 as a quick test of fitness?

The burpee began as Royal H. Burpee's gentle four-count move for his Columbia University doctoral thesis; the push-up and jump that make it so punishing arrived in later variants.

Which beginner running plan, written by Josh Clark in 1996, became a free NHS app?

Couch to 5K builds over nine weeks from run-walk intervals to 30 minutes of non-stop running; Clark, a new runner himself, designed it to coax his fifty-something mother off the sofa.

American Charles Osborne's record-setting attack of hiccups lasted how long?

Osborne hiccupped for 68 years: the attack began in 1922 as he readied a hog for slaughter, and it stopped in 1990, a year before his death, after an estimated 430 million hiccups.

Sir William Cubitt introduced the treadmill in 1818 for use in which institutions?

Cubitt's 1818 treadwheel was built for prisons: seeing inmates idle at Bury St Edmunds gaol, he set them climbing an endless staircase to grind grain, and the major gaols of Britain soon adopted it.

Russian kettlebells are traditionally weighed in which unit, equal to about 16.4 kg?

The pood, about 16.4 kg, is the traditional kettlebell unit; the girya began life as a counterweight for weighing crops in 18th-century Russian markets before strongmen picked it up.

The WWII tale that carrots gave RAF pilots night vision is widely said to have been cover for what?

Radar is the usual answer: the press credited night-fighter ace John 'Cat's Eyes' Cunningham's kills to carrots while airborne sets stayed secret, though an RAF Museum curator doubts the tale was ever meant to fool the Germans.

Joseph Pilates originally called his exercise method what?

Contrology was Joseph Pilates's own name for the system he began working out while interned in Britain as a German national during the First World War, drilling fellow inmates in the mat exercises at its core.

US Air Force physician Kenneth Cooper coined which fitness word, the title of his 1968 book on endurance exercise?

Aerobics grew out of Cooper's puzzle that strong men often did badly at running and swimming; he measured how well bodies use oxygen and built a points system around running, walking, swimming and cycling.

Which actress's 1982 Workout tape became a home-video bestseller and helped sell VCRs?

Jane Fonda filmed a routine devised by Leni Cazden that the two taught at their Beverly Hills studio; it became the first of 22 videos that together sold more than 17 million copies.

Which free weekly 5K began with 13 runners in south-west London in 2004?

Parkrun began as the Bushy Park Time Trial, set up by Paul Sinton-Hewitt while he was out of work and too injured to run himself; it has stayed free and volunteer-led as it spread to more than 20 countries.

Which soft drink did Atlanta pharmacist John Pemberton launch in 1886 as a patent medicine for headaches?

Coca-Cola began as a non-alcoholic rewrite of Pemberton's French Wine Coca, forced on him by Atlanta's new temperance law. He sold the rights shortly before he died in 1888.

Which Bee Gees hit do first-aid trainers use to time CPR because its beat matches the recommended rhythm?

Stayin' Alive runs at about 103 beats per minute, inside the 100 to 120 chest pushes a minute that rescuers are taught. Trainees who learn with the tune also remember the skill better months later.

Which animal appears on the staff at the centre of the World Health Organization's emblem, an ancient Greek symbol?

The snake belongs to Asclepius, the Greek god of healing, whose cult made use of live snakes. The WHO shows it coiled round his staff, set over the United Nations' map of the world.

'Sphenopalatine ganglioneuralgia' is the scientific term for which brief pain, common in migraine sufferers?

Brain freeze fades within a couple of minutes, and pressing the tongue against the roof of the mouth to warm it is the standard trick for hurrying it along.

Which antibiotic, found by chance in 1928, was turned into a usable drug by Howard Florey's team at Oxford?

Penicillin turned up when mould spoiled one of Alexander Fleming's culture plates, but it stayed a curiosity until the Oxford team purified it in 1940. Fleming, Florey and Ernst Chain shared a Nobel Prize.

Which breakfast cereal was created for patients at John Harvey Kellogg's Battle Creek Sanitarium in Michigan?

Corn flakes later split the Kellogg brothers: Will wanted to add sugar and sell them to the public, while John, the sanitarium's health-reforming doctor, was opposed.

Which German word, borrowed into American English, literally means 'health'?

Gesundheit is what German speakers say after a sneeze. Spanish 'salud' and Italian 'salute' work the same way, wishing the sneezer well rather than blessing them.

Arctic explorers have been poisoned by eating polar bear liver, which holds a toxic overdose of which nutrient?

Vitamin A builds up in the organs of top Arctic predators, which is why Inuit hunters have long refused to eat the liver of a polar bear or a bearded seal.

Which medicine-cabinet staple did Johnson & Johnson cotton buyer Earle Dickson invent for his accident-prone wife?

Band-Aid began in 1920 as squares of gauze that Dickson spaced along a roll of tape, so his wife Josephine could dress her own kitchen cuts. The idea made him a company vice president.

Which word for isolating the sick comes from the forty days that ships had to wait off plague-era Venice?

Quarantine comes from the Venetian 'quarantena', meaning forty days. Crews and cargo arriving from plague ports had to sit out the wait at anchor before anyone could come ashore.

Florence Nightingale earned the nickname 'the Lady with the Lamp' nursing British soldiers in which war?

In the Crimean War, her hospital at Scutari lost ten times more soldiers to illnesses such as typhus than to battle wounds. Nightingale showed it in charts and became the Royal Statistical Society's first female member.

Which disease, the only human one ever wiped out, did the World Health Organization declare eradicated in 1980?

Smallpox infects only humans in nature, so a global vaccination drive left it nowhere to hide: the last natural case came in 1977. The only other eradicated disease, rinderpest, struck cattle.

Which substance, at about 96 per cent mineral, is the hardest in the human body?

Enamel has no way to regenerate, so a chipped or worn tooth cannot grow its coating back the way a broken bone knits itself together.

Which painkiller, sold by Bayer since 1899, is a synthetic cousin of a compound found in willow bark?

Aspirin was Bayer's brand name for acetylsalicylic acid, but the company lost or sold its rights to the trademark in many countries, which is why any maker there can use the word.

Which form of radiation did Wilhelm Röntgen discover in 1895 and use to photograph the bones of his wife's hand?

X-rays took their name from the symbol for an unknown, because Röntgen had no idea what the radiation was. On seeing the picture of her hand, his wife said, 'I have seen my death.'

Which medical instrument did French doctor René Laennec invent in 1816 from a rolled-up sheaf of paper?

The stethoscope began as a paper cylinder that Laennec held to a young woman's chest. He heard her heart more clearly than he ever had with an ear pressed to a patient, and without the embarrassment.

Which blood type, given in emergencies when a patient's own type is unknown, is called the 'universal donor'?

O negative red cells carry none of the A, B or RhD markers that a recipient's immune system could attack. AB positive is the mirror image, the universal recipient.

Which word familiar from modern drug trials comes straight from the Latin for 'I shall please'?

Placebo pills contain no drug, yet can ease symptoms through expectation alone. The trick also runs in reverse: an inert pill that makes people feel worse because they expect harm is a nocebo.

Which hormone did Frederick Banting's Toronto team first inject into a dying 14-year-old boy in 1922?

Insulin's first patient was Leonard Thompson, who lay dying of diabetes in Toronto General Hospital. Its discoverers then sold the patent to the University of Toronto for a token dollar.

Which anaesthetic, nicknamed 'laughing gas', did dentist Horace Wells test in 1844 by having his own tooth pulled?

Nitrous oxide got its nickname from the chemist Humphry Davy. Wells saw it at a travelling show, and the very next day let a colleague pull his wisdom tooth while he breathed it from a bag.

Which muscle, the largest in the human body, holds the trunk upright and lets humans stand erect?

Gluteus maximus is unusually big in humans. Other primates have much flatter hips and cannot stay standing, so the muscle that shapes the buttocks is a signature of walking on two legs.

Which butterfly-shaped gland in the neck releases the hormones that set the body's metabolic rate?

Thyroid hormones cannot be made without iodine, and worldwide a shortage of it is the most common cause of an underactive gland. That is why many countries add iodine to table salt.

Which disease's name comes from the Italian for 'bad air', a relic of the belief that swamp fumes caused it?

Malaria kept its 'bad air' name even after 1897, when Ronald Ross found the parasite inside a mosquito and showed that the swamps were guilty only of breeding them.

Which disease's vaccine did Jonas Salk decline to patent in 1955, asking 'Could you patent the sun?'

Polio's vaccine made Salk a hero overnight when its success was announced. Asked on television who owned the patent, he answered, 'Well, the people, I would say.'

Which Latin-dance workout did Colombian instructor Beto Pérez create after forgetting his usual aerobics music?

Zumba grew out of the salsa and merengue cassettes Pérez happened to have with him in Cali that day. He first called the class 'Rumbacize'.

Which fifth basic taste did Tokyo chemist Kikunae Ikeda identify in 1908 while studying kelp broth?

Umami is the savoury taste of glutamate. A year after Ikeda named it, his discovery went on sale as Ajinomoto, the world's first seasoning built on it: MSG.

Which fruit carries warnings on many medicine labels because its compounds block an enzyme that breaks drugs down?

Grapefruit contains furanocoumarins that knock out CYP3A4, an enzyme that processes almost half of all drugs, so an ordinary dose can build up in the blood like an overdose.

Which sweet food should babies under one year old never be given, because it can carry botulism spores?

Honey can hold dormant spores that grow inside a young baby's intestines and release their toxin there. After the first birthday it is considered safe.

Irish-born cook Mary Mallon, held in isolation in New York for over two decades, was nicknamed after which disease?

Typhoid never made Mallon ill herself. She was the first person in the US identified as a symptom-free carrier, and she is believed to have infected up to 57 people through her cooking.

In which South African city did surgeon Christiaan Barnard perform the first human heart transplant in 1967?

Cape Town's Groote Schuur Hospital hosted the operation. Patient Louis Washkansky woke and talked with his wife, but died 18 days later of pneumonia as anti-rejection drugs weakened his defences.

Which disease did London doctor John Snow trace to a contaminated water pump on Broad Street in 1854?

Cholera was widely blamed on foul air, or 'miasma', until Snow's study of the deaths around one Soho pump made the case that tainted water was carrying it.

Which wellness practice, known in Japan as 'shinrin-yoku', did a government ministry begin promoting in the 1980s?

Forest bathing means spending unhurried time among trees. Tomohide Akiyama, head of Japan's Forestry Agency, coined the term in 1982 to encourage more people to visit the country's woods.

Which bitter compound from cinchona bark gives tonic water its taste and makes it glow under a UV lamp?

Quinine was first stirred into fizzy water as a guard against tropical fever. Modern tonic holds far less of it, and far more sweetener, than the original medicinal version.

What makes the 'lub-dub' sound of a human heartbeat that a doctor listens for through the chest wall?

Valves snapping shut make both beats. 'Lub' is the pair between the upper and lower chambers closing, and 'dub' is the two exit valves closing a moment later.

'Borborygmus', from a Greek word that probably imitates the sound, is the scientific name for which bodily noise?

Stomach rumble is the sound of muscle contractions pushing the gut's contents along. It grows louder about two hours after the stomach empties, when a fresh wave sweeps through to clear leftovers.

A knock on the elbow's so-called 'funny bone' actually jolts which nerve, left unprotected as it passes the joint?

Ulnar is the name of the largest nerve in the body that no muscle or bone shields, which is why a bump there sends a tingle down to the ring and little fingers.

People who inherit the reflex nicknamed 'ACHOO syndrome' sneeze when suddenly exposed to what?

Bright light, most often stepping out into sunshine, sets off the photic sneeze reflex. It runs in families as a dominant trait, so one affected parent gives a child a 50 per cent chance of it.

The word 'spa' comes from the name of a mineral-springs town in which European country?

Belgium's town of Spa, a health resort since the 14th century, was so famous for its waters that its name became the word for any resort built around a spring.

In the ancient Greek theory of the four humours, too much black bile was said to produce which temperament?

Melancholy is simply the Greek for 'black bile'. Old medicine blamed gloom on an excess of the fluid, which was thought to seep from the spleen.

Which operation, one of the oldest known to archaeology, involves drilling or scraping a hole into the skull?

Trepanation was survivable even in the Stone Age: Neolithic skulls show new bone grown around the rim of the hole, proof that the patient lived on after the operation.

Which Swiss Alpine town, host of the World Economic Forum since 1971, first grew famous as a resort for lung patients?

Davos drew tuberculosis sufferers such as Robert Louis Stevenson to its mountain air, and one of its sanatoriums inspired the clinic in Thomas Mann's novel The Magic Mountain.

Doctor Barry Marshall drank a broth of Helicobacter pylori in 1984 to help prove the microbe causes which condition?

Peptic ulcers had been blamed on stress, spicy food and excess acid. Marshall expected an ulcer years later; instead he felt sick within three days, and the work won a 2005 Nobel Prize.

Which Persian physician completed The Canon of Medicine in 1025, a standard textbook in Europe for centuries?

Avicenna, or Ibn Sina, filled five books with the medicine of his day. Translated into Latin in 12th-century Toledo, they were still a standard textbook in Europe into the 1700s.

The Apgar score, devised by anaesthetist Virginia Apgar in 1952, is a quick check on the condition of whom?

Newborns are scored at one and five minutes after birth on breathing, skin colour, reflexes, movement and heart rate. Apgar's surname was later turned into a memory aid for the five signs.

Which disease, caused by a lack of thiamine, was long common where people lived mostly on white rice?

Beriberi may get its name from a Sinhalese phrase meaning 'I cannot, I cannot', after the weakness it brings. It swept Japan once polished rice went from an upper-class luxury to an everyday staple.

Which hands-on therapy did magnetic healer D. D. Palmer found in Davenport, Iowa, in the 1890s?

Chiropractic rests on Palmer's hunch that adjusting the spine could cure disease. He claimed the idea was passed to him from 'the other world' by a doctor who had died 50 years earlier.

The prescription symbol 'Rx' stands for the Latin word 'recipe', which gave a pharmacist which one-word instruction?

Take was the word doctors wrote at the head of a prescription, an order to gather the ingredients listed below it. 'Recipe' did not mean cooking instructions until the 1700s.

The proverb 'An apple a day keeps the doctor away' grew from a rhyme first recorded in 1866 in which country?

Wales gave us the original, noted down in Pembrokeshire: 'Eat an apple on going to bed, and you'll keep the doctor from earning his bread.' The shorter wording came later.

Which Greek physician to Roman emperors shaped Western medicine for more than 1,300 years after his death?

Galen could not legally dissect people, so he described the body from Barbary apes. His anatomy went uncontested until 1543, when Andreas Vesalius published drawings made from human dissections.

Which woman was the unwitting source, in 1951, of the 'HeLa' cells still grown in research labs around the world?

Henrietta Lacks was being treated for cervical cancer in Baltimore when a biopsy was cultured without her knowledge. Hers were the first human cells seen to keep dividing in a lab without dying.