141 Fun Facts About Nutrition

Which of these nutrients is classed as a macronutrient?

Carbohydrates, protein and fat are the macronutrients because the body needs them by the gram, mainly for energy; vitamins and trace minerals are needed only in milligrams or less, so they are micronutrients.

What is a primary function of protein in the human body?

Building and repairing tissues is protein's central job: the body is always breaking its own proteins down and making new ones, so it needs a fresh supply of amino acids from food every day.

Which of these foods ranks lowest on the glycemic index, where glucose scores 100?

Lentils score about 30, well under half the figure for cornflakes or white bread, because their starch is digested slowly, so blood sugar rises gently instead of spiking.

Which type of fat is generally associated with benefits for heart health?

Monounsaturated fat helps lower 'bad' cholesterol when it takes the place of saturated fat, which is why heart advice is to swap butter and other solid fats for liquid plant oils.

What is a key role of dietary fiber in the digestive system?

Promoting regular bowel movements is fiber's best-known job: the body cannot digest it, so it adds bulk to the stool and helps it pass, which prevents constipation.

Which of these minerals is a main building block of the hydroxyapatite in bones and teeth?

Phosphorus is the phosphate in hydroxyapatite, the hard crystal of bone and tooth enamel; that is why ground bone meal works as a slow-release phosphorus fertilizer.

Which characteristic defines a 'complete protein'?

It contains all nine essential amino acids, the ones the body cannot make. Most plant proteins run short of at least one, but they complement each other, which is why rice with beans adds up to a complete set.

Which organ produces insulin, the hormone that lowers blood glucose?

The pancreas makes insulin in the beta cells of its islets of Langerhans; insulin lets muscle, fat and liver cells take up glucose from the blood.

Which of these vitamins is recognized for antioxidant properties that protect cells?

Vitamin E dissolves in fat, so it lodges in cell membranes, where it hands a hydrogen atom to free radicals and stops them setting off chain reactions in the membrane's own fats.

Beriberi is a severe, chronic disease caused by a deficiency of which nutrient?

Beriberi is caused by a lack of Vitamin B1 (thiamine). It was common wherever polished white rice was the staple, because milling strips away the thiamine-rich outer layers of the grain.

Sunflower, corn and soybean oils are major sources of which family of polyunsaturated fats?

Omega-6 fats, chiefly linoleic acid, fill sunflower, corn and soybean oils; linoleic acid is one of only two fatty acids the body cannot make, so it has to come from food.

What is the primary function of Vitamin K in the body?

Aiding blood clotting is vitamin K's main job, and the K comes from 'koagulation'; newborns are given a vitamin K injection because little crosses the placenta and their clotting factors are low.

Which group of nutrients, often added to energy drinks, helps enzymes release energy from food?

B vitamins work as coenzymes that help release energy from food but supply none themselves; an energy drink's kick comes from its caffeine and sugar.

Which vitamin greatly boosts the absorption of iron from plant foods such as beans and spinach?

Vitamin C keeps plant iron in a soluble form the gut can absorb, so eating citrus, peppers or other vitamin C-rich foods with beans or greens raises the iron you take in.

Omega-3 fatty acids such as DHA are best known for supporting the development of which part of the body?

Nervous system: DHA is built into the membranes of brain and retinal cells and accumulates in the fetal brain in late pregnancy, which is why it is now added to infant formula.

In nutrition, what is a calorie a measure of?

Energy content is what a calorie measures: food energy was first found by burning a dried sample in a sealed 'bomb calorimeter' and recording how much the surrounding water warmed.

Which type of dietary fiber forms a gel in the gut and helps lower cholesterol?

Soluble fiber turns to a gel that slows digestion and helps lower cholesterol; the evidence for oats was strong enough that in 1997 the FDA let them carry a heart-health claim.

Which of these foods has more potassium per serving than a banana?

Dried apricots beat the banana comfortably, and so does a baked potato with its skin; the banana's reputation outruns it, since per serving it supplies only a moderate amount.

The human body can make which nutrient in its skin when exposed to sunlight?

Vitamin D forms when the sun's ultraviolet B rays strike a cholesterol compound in the skin; at high latitudes the winter sun is too weak to do the job, so food and supplements must fill the gap.

A chronically high intake of which mineral is most associated with hypertension and cardiovascular disease?

Sodium makes the body hold on to water, which swells the volume of blood and the pressure on vessel walls; most of it comes from packaged and prepared food, not the salt added at the table.

Which type of cholesterol is nicknamed 'good' because it carries cholesterol away from the arteries?

HDL, high-density lipoprotein, ferries surplus cholesterol back to the liver, which removes it from the body; the larger lipoproteins deliver fats to the tissues instead.

Pellagra is a disease caused by a deficiency of which B vitamin?

Niacin (B3) deficiency causes pellagra, which was epidemic in the American South in the early 1900s; Joseph Goldberger showed it came from a poor, corn-based diet, not a germ.

Which type of fat did the US FDA rule unsafe in its artificial form in 2015?

Trans fat raises 'bad' cholesterol while lowering the 'good' kind; in 2015 the FDA ruled that partially hydrogenated oils, which supplied most of the artificial kind, were no longer recognized as safe, so food makers had to drop them.

Which vitamin must strict vegans get from supplements or fortified foods?

Vitamin B12 is made by microbes, not by plants, and reaches people through meat, fish and eggs; vegans are therefore advised to use fortified foods or a supplement.

Which enzyme in saliva starts digesting starch before food even leaves the mouth?

Amylase in saliva begins splitting starch into sugars as you chew, which is why plain rice or potato held in the mouth slowly starts to taste sweet.

Which term describes how many vitamins and minerals a food supplies per calorie?

Nutrient density favours leafy greens: when a CDC-journal study scored produce this way, watercress came top, while citrus fruits and berries landed in the bottom half.

Foods that supply energy but little protein, fibre or vitamins are said to contain what?

Empty calories come from sugar and solid fats that bring little or no protein, fibre, vitamins or minerals, which makes it hard to eat a balanced diet without overshooting on energy.

Which sweetener should never be fed to babies under a year old because it can carry botulism spores?

Honey can carry spores of the botulism bacterium; in a baby's immature gut they can grow and release toxin, so health agencies say no honey before 12 months.

Live bacteria eaten in foods like yogurt for their health benefits are known by what name?

Probiotics are live microbes taken for the benefit of the host. The idea took off around 1907, when Élie Metchnikoff argued that Bulgarian peasants owed their long lives to the bacteria in their yogurt.

Which macronutrient provides the most energy per gram?

Fat delivers about 9 kilocalories per gram, more than double the roughly 4 per gram from protein or starches. Alcohol sits between them at about 7.

Who typically has the highest share of body water?

A newborn baby is about three-quarters water, against roughly 60% for an adult man; the share falls with age and with body fat, since fat tissue holds far less water than lean tissue.

Which mineral is a key component of hemoglobin, essential for oxygen transport in the blood?

Iron sits in the heme groups of hemoglobin, where it binds oxygen; most of the body's iron is in red blood cells, which is why menstruation and frequent blood donation are common routes to deficiency.

Which intake level is set to cover the needs of nearly all healthy people?

The Recommended Dietary Allowance (RDA) was born in the Second World War, when a US committee studying wartime nutrition drew up the first set.

A deficiency of which mineral is known to cause goiter?

Iodine is the raw material of thyroid hormones; when it runs short, the pituitary keeps signalling the thyroid to work harder, and the overstimulated gland swells into a goiter.

Which of these foods counts as a whole grain?

Popcorn is a whole grain because the entire corn kernel is popped with nothing milled away; the tough bits of hull that catch in your teeth are its outer layer, still attached.

Which mineral is involved in over 300 enzymatic reactions, including muscle and nerve function?

Magnesium is needed for more than 300 biochemical reactions and helps nerves and muscles work normally, so a shortage shows up as muscle cramps, spasms and twitches.

Which vitamin is particularly important for maintaining good vision, especially in low light conditions?

Vitamin A is needed to make rhodopsin, the light-catching pigment of the retina's rod cells, which is why night blindness is one of the earliest signs of deficiency.

A deficiency of which nutrient during pregnancy is strongly linked to neural tube defects in infants?

Folate is needed in the first weeks after conception, often before a woman knows she is pregnant, which is why the US has required folic acid in enriched flour and cereals since 1998.

Which substance made by the liver helps the body digest and absorb fats?

Bile, made by the liver and stored in the gallbladder, works like a detergent: it breaks fat into tiny droplets that digestive enzymes can then attack.

The majority of nutrient absorption in the human digestive system occurs in which organ?

The small intestine, with its extensive surface area provided by villi and microvilli, is where the vast majority of nutrient absorption takes place in the digestive system.

Which of these is a common symptom of dehydration?

Headaches and fatigue are early signs of dehydration, but thirst is not a reliable alarm: some older adults lose their sense of thirst, so they can dry out without feeling it.

Which simple sugar is the sweetest of the common dietary sugars?

Fructose is the sweetest of the natural sugars, which is why food makers use enzymes to turn some of the glucose in corn syrup into it, creating high-fructose corn syrup.

The DASH diet is primarily recommended for managing or preventing which health condition?

High blood pressure is the target: DASH stands for Dietary Approaches to Stop Hypertension, and in its first trial the diet lowered blood pressure even though participants' weight did not change.

People with celiac disease must avoid wheat, barley and which other grain?

Rye completes the trio of grains that trigger celiac disease; buckwheat, despite its name, is not closely related to wheat and is safe to eat.

Which mineral, sold in lozenges as a cold remedy, is needed for taste and smell?

Zinc is needed by many enzymes and by the immune system; a shortage dulls taste and slows wound healing, and zinc lozenges may shorten a cold.

Which enzyme breaks down the sugar in milk?

Lactase splits milk sugar in the gut; without enough of it the sugar reaches the colon, where bacteria ferment it. Most adults worldwide make less lactase after infancy, so lactose intolerance is the global norm.

On the USDA's 2011–2026 MyPlate graphic, which food group sat in the small side cup?

Dairy sat in the small cup beside the plate that fruits, vegetables, grains and protein shared; the 2026 guide that replaced MyPlate raised it to the top of its diagram, alongside protein and vegetables.

Which pigment gives sweet potatoes, pumpkins and mangoes their orange colour?

Beta-carotene is such a strong orange pigment that eating a great deal of it can tint the skin itself yellow-orange, a harmless and reversible condition called carotenosis.

Which acid makes gastric juice harsh enough to kill most swallowed bacteria?

Hydrochloric acid gives gastric juice its bite; besides killing microbes, it switches the protein-digesting enzyme pepsin from its inactive form into its active one.

Despite its name, a peanut is botanically what kind of plant food?

A peanut is a legume whose pods grow underground, which is why Linnaeus named the species hypogaea, Greek for 'under the earth'.

Which protein network makes wheat dough stretchy and lets bread rise?

Gluten forms when wheat flour is wetted and kneaded; its elastic network traps the carbon dioxide that yeast gives off, so the dough rises and holds its shape.

Which mineral is the main positively charged ion inside human cells?

Potassium is the principal intracellular cation: the sodium-potassium pump keeps potassium concentrated inside cells and sodium outside, a gradient that nerves and muscles depend on.

Cavities form when bacteria living on your teeth break down sugar and produce what?

Mouth bacteria ferment sugar into acid, which dissolves tooth enamel; saliva constantly rebuilds enamel, so decay wins only when the dissolving outpaces the repair.

A whole grain keeps all three parts of the kernel: the bran, the germ and what else?

The endosperm is the starchy bulk of the kernel that refined grains keep while discarding bran and germ; a brown loaf proves nothing, since some are simply coloured with molasses.

Which sugar, made of two glucose units, builds up in sprouting barley?

Maltose is named after malt, the sprouted barley in which it builds up as the grain's starch breaks down; brewers then feed it to yeast to make beer.

Which of these fruits is unusually rich in monounsaturated fat?

Avocado gets about three-quarters of its calories from fat, roughly two-thirds of it monounsaturated; coconut is fatty too, but its fat is mostly the saturated kind.

Which mineral is the most abundant in the human body?

Calcium is the body's most abundant mineral, with about 99% of it in bones and teeth; when the diet runs short, the body 'borrows' calcium from the skeleton to keep blood levels steady.

In what chemical form is most fat stored in the body and found in food?

Triglycerides are three fatty acids on a glycerol backbone; calories the body does not need right away, whatever food they came from, are converted into them and stored in fat cells.

The word 'vitamin' was coined by joining the Latin for 'life' to the name of which class of chemicals?

Amines gave 'vitamine' its ending: Casimir Funk assumed these vital nutrients were all amines. Once it was clear that not all were, the final 'e' was dropped.

Which other vitamin joins A, D and E as fat-soluble?

Vitamin K joins A, D and E as the fat-soluble vitamins; they are absorbed along with dietary fat, so people whose gut absorbs fat poorly risk running short of all four.

Eating large amounts of which raw food can cause a deficiency of vitamin B7?

Egg whites contain avidin, a protein that grips vitamin B7 so tightly the gut cannot absorb it; cooking breaks avidin down, so only raw whites cause trouble.

Which B vitamin is the mainstay of 'hair, skin and nails' supplements?

Biotin, vitamin B7, is sold for hair and nails because a deficiency thins the hair; yet evidence that supplements help people who are not deficient is inconclusive.

Which red pigment gives tomatoes their colour?

Lycopene is one nutrient that cooking improves: heating tomatoes in oil makes it easier to absorb, so the body gets more from sauce or paste than from raw fruit.

Which amino acid, blamed for post-Thanksgiving drowsiness, can the body convert into niacin?

Tryptophan converts to niacin at about 60 mg to 1 mg; turkey holds no more of it than other meats, so the holiday slump may owe more to the carbohydrate-heavy meal around it.

Which of these is so rich in selenium that a single one can exceed an adult's daily requirement?

A Brazil nut can hold more selenium than an adult needs in a day, though the amount swings with the soil; eating handfuls regularly risks selenium poisoning, whose signs include brittle hair and nails.

Milk sugar is made of glucose joined to which other simple sugar?

Galactose makes up half of milk sugar; babies born with galactosemia cannot break it down and can fall seriously ill within days of their first milk feeds, which is why newborns are screened for it.

Which nutrient got its first US dietary intake recommendations only in 1998?

Choline received its first Adequate Intake from the US Institute of Medicine in 1998; it is a structural part of cell-membrane phospholipids and is not formally classed as a vitamin, though humans cannot make enough of it.

Which metal sits at the centre of the vitamin B12 molecule?

Cobalt sits at the centre of vitamin B12, hence the name cobalamin; the molecule is so intricate that mapping it with X-rays helped win Dorothy Hodgkin the 1964 Nobel Prize in Chemistry.

The ketogenic diet was developed in the 1920s to treat which condition in children?

The ketogenic diet was designed in the early 1920s to mimic fasting, which was known to calm epilepsy; it fell from favour once the anticonvulsant phenytoin proved itself in the late 1930s.

Broccoli, kale and Brussels sprouts all belong to which family of vegetables?

The cabbage family is also called cruciferous, 'cross-bearing', after its four-petalled flowers; broccoli, kale, cabbage and Brussels sprouts are all one species, bred into different shapes.

In a 2016 redesign, US Nutrition Facts labels gained a separate line for which ingredient?

Added sugars got their own line, with a percent Daily Value, in the 2016 update; vitamins A and C were dropped from the required list because deficiencies had become rare.

People with PKU must restrict which amino acid, named on diet soda cans?

Phenylalanine builds up to brain-damaging levels in PKU because the enzyme that breaks it down is missing; diet sodas carry a warning because the sweetener aspartame contains it.

Marathon runners 'carb-load' to top up the liver and muscle stores of which form of glucose?

Glycogen is how the body banks glucose, and the supply is limited; when it runs out late in a race, marathon runners 'hit the wall'.

Which 'hunger hormone' is made mainly by the stomach?

Ghrelin, released mainly by the stomach when it is empty, peaks in the blood just before meals and falls after eating; it also prompts the pituitary to release growth hormone.

The body mass index is a person's weight divided by the square of which measurement?

Height squared is the divisor Adolphe Quetelet chose; because the index cannot tell muscle from fat, lean athletes and bodybuilders can score as overweight.

An adult with a BMI of 32 falls into which weight category?

Obese is the label for a BMI of 30 or more, with 25 to 29.9 classed as overweight; the WHO adds lower trigger points for Asian populations, whose health risks rise at smaller BMIs.

Which seed yields an oil that is more than half omega-3 fat?

Flax seed oil, also called linseed oil, is over half omega-3 ALA; the reactivity that turns it rancid quickly also lets it dry into the hard film that binds oil paints and wood varnishes.

Which hormone that signals fullness is made mainly by fat cells?

Leptin, named from the Greek leptos ('thin'), rises with the amount of body fat; in obesity the brain grows resistant to its signal, much as tissues become resistant to insulin.

Which staple root must be soaked or fermented to remove cyanide before eating?

Cassava roots contain compounds that release cyanide, so they must be soaked, fermented or thoroughly cooked; a diet of poorly processed bitter cassava can cause konzo, a sudden and permanent paralysis of the legs.

Which trace element is built into the antioxidant enzyme glutathione peroxidase?

Selenium, as the amino acid selenocysteine, sits in the active site of glutathione peroxidase, which disarms hydrogen peroxide; severe deficiency causes Keshan disease, a heart condition first described in China.

Removing which organ, the source of 'intrinsic factor', leaves a person needing vitamin B12 injections?

The stomach's parietal cells make intrinsic factor, which escorts B12 through the gut to the ileum, where it is absorbed; in pernicious anemia the immune system destroys those cells, with the same result.

Australian food labels use which unit, about 4.2 to the calorie?

Kilojoules are the metric counterpart of the calorie: one food calorie equals about 4.2 of them, which is why the figure on an Australian snack looks roughly four times bigger than the calorie count Americans see.

Which ion is added to many public water supplies to reduce tooth decay?

Fluoride strengthens tooth enamel; community water fluoridation began in 1945 after studies of children in areas where the ion occurs naturally, and too much causes mottled teeth (fluorosis).

An excess of which vitamin turns urine bright yellow?

Riboflavin (vitamin B2) is itself a yellow-orange powder, used as the food colouring E101; the excess excreted in urine gives the bright yellow effect called flavinuria.

Eating the liver of which Arctic animal is notorious for causing acute vitamin poisoning?

Polar bear liver holds so much vitamin A that a single meal can cause acute hypervitaminosis; Dutch explorer Gerrit de Veer recorded his crew falling ill from it on Novaya Zemlya in 1597.

What name is given to the energy the body burns at complete rest just to stay alive?

Basal metabolic rate is the largest slice of the calories most people burn, typically well over half of the daily total and far more than exercise accounts for.

The 36 volunteers half-starved in the 1944–45 Minnesota Starvation Experiment were all what?

Conscientious objectors volunteered to be half-starved so that Ancel Keys's team could learn how best to feed Europe's famine victims back to health after the war.

Which family of proteins makes up about 80% of the protein in cow's milk?

Casein makes up about 80% of the protein in cow's milk, with whey the rest; in cheese-making, rennet makes the casein clump into solid curds.

Drinking far too much water dilutes the blood and causes which condition?

Hyponatremia means blood sodium has fallen too low: water floods into cells and makes them swell, the brain's included.

US Nutrition Facts labels base their % Daily Values on how many calories a day?

The 2,000-calorie figure is only a yardstick: the label's own footnote says it is 'used for general nutrition advice', because real needs run higher or lower with age, sex, size and activity.

Kwashiorkor is a word from the Ga language of which country, once the Gold Coast?

Ghana's Ga language gave the word, roughly 'the sickness of the child displaced by a new baby'; Cicely Williams, who named the condition in 1935, saw it strike toddlers weaned when a sibling arrived.

British sailors were nicknamed 'limeys' after the citrus juice added to their grog to prevent which disease?

Scurvy killed an estimated two million sailors between 1500 and 1800. The Royal Navy's later switch from lemons to weaker limes meant the grog stopped working.

The West African 'miracle berry' temporarily makes lemons, limes and other sour foods taste how?

Lemons taste sweet because miraculin, a protein in the berry, binds to the tongue's sweetness receptors. The effect fades as saliva washes the protein away.

Which vegetable gives urine a distinctive sulphurous smell within about half an hour of being eaten?

Asparagus compounds break down into sulphur chemicals such as methanethiol within 15 to 30 minutes. In surveys, only 40% to 79% of people report noticing the odour.

Which fruit does botany exclude from the true berries, a group that includes bananas, grapes and aubergines?

Strawberry flesh grows from the flower's receptacle rather than its ovary, and each 'seed' on the outside is itself a tiny fruit called an achene.

Which compound gives chilli peppers their burn, yet has no effect on the birds that spread their seeds?

Capsaicin sets off a heat-sensing channel in mammals that does not respond in birds. The hottest part of a chilli is the white pith, not the seeds.

Which stimulant, the world's most widely consumed psychoactive drug, occurs naturally in kola nuts?

Caffeine keeps people alert by blocking adenosine, a brain chemical with a depressant effect. Its shape is close enough to adenosine's to fit the same receptors.

Babies under one year old should never be fed honey because of the risk of which illness?

Botulism spores are often present in honey, and a baby's gut bacteria are too sparse to stop them growing. Honey plays a part in a fifth of infant cases.

Which documentary followed Morgan Spurlock as he ate only McDonald's food, three times a day, for a month?

Super Size Me left Spurlock 24.5 pounds heavier, and McDonald's dropped its supersize portions six weeks after the film came out.

Which painful joint condition, long nicknamed 'the disease of kings', is linked to beer, shellfish and liver?

Gout flares when uric acid from purine-rich food and drink forms needle-shaped crystals in a joint. In about half of cases, that joint is the base of the big toe.

Which breakfast fruit carries pharmacy warnings because it blocks an enzyme that breaks down many medicines?

Grapefruit contains furanocoumarins, which knock out CYP3A4, the enzyme that processes almost half of all drugs. Even one small glass of juice can matter.

Which cereal grain, first domesticated along China's Yangtze River, is the staple food of over half the world?

Rice is overwhelmingly an Asian crop: about 90% of it is grown there, and China and India together produce roughly half the world's supply.

Tofu, eaten in China for over 2,000 years, is made by curdling a milk pressed from which bean?

Soybean milk is curdled and the curds pressed into blocks, much as cheese is made. Tofu making was first recorded during China's Han dynasty.

Kombucha, the fizzy drink fermented with a culture called a SCOBY, starts out as which sugared beverage?

Black tea and sugar feed the SCOBY, a mat of bacteria and yeast that is nicknamed a mushroom but is not one. The drink is believed to have originated in China.

Which spice from the ginger family gets its deep yellow colour from the compound curcumin?

Turmeric was first used as a dye and still colours the robes of monks in India. No high-quality clinical evidence shows that eating it treats any disease.

Which breakfast cereal did the Kellogg brothers develop in the 1890s for patients at the Battle Creek Sanitarium?

Corn flakes began as a wheat cereal meant to counter indigestion. John Harvey Kellogg alone was named on the 1896 patent, and his brother Will long argued he deserved more credit.

Which sugar substitute is extracted from the leaves of a plant long used by the Guaraní people of Paraguay?

Stevia is about 50 to 300 times sweeter than sugar, yet humans cannot metabolise its glycosides, so it supplies no calories.

Which childhood disease of soft, bowed leg bones was once treated with daily spoonfuls of cod liver oil?

Rickets was common into the 20th century. Breast-fed babies who get little sunlight are among those most at risk today.

Which plant oil, a white solid below about 25 °C, do health bodies advise limiting for its saturated fat?

Coconut oil is only about 8% unsaturated fat, and studies find its health effects resemble those of butter and beef fat.

Which substance supplies about seven calories per gram, nearly twice as much as sugar or protein?

Alcohol, or ethanol, carries 29 kilojoules in every gram. The polyol sweeteners in sugar-free gum supply only about a third as much.

What collective name covers the dissolved minerals lost in sweat and replaced by sports drinks?

Electrolytes carry an electric charge in body fluids, which is what activates nerves and muscles. Too few can cause muscle weakness or severe contractions.

What is the feeling of fullness after a meal, signalled by the vagus nerve and gut hormones, called?

Satiety lasts until the next meal, whereas satiation is the moment a meal ends. One gut hormone involved, cholecystokinin, is produced in response to fat and protein.

Gelatin, which makes jelly and gummy bears set, is derived from which protein in animal skin and bones?

Collagen is the most abundant protein in mammals, making up 25% to 35% of all the protein in the body.

Which watery by-product of cheese-making is dried into a protein powder sold for building muscle?

Whey isolate powders are typically over 90% protein by dry weight. The same liquid is also made into ricotta and Norway's brunost.

Which seed from the Andes is cooked like a grain although it is botanically related to spinach?

Quinoa is a pseudocereal, not a grass. It may have been domesticated twice: once in the high Andes and again in the lowlands of Chile and Argentina.

Which food is made by fermenting milk with Lactobacillus bulgaricus and Streptococcus thermophilus bacteria?

Yogurt takes its name from an Ottoman Turkish root meaning 'to condense'. France allows the label only for milk fermented by exactly those two bacteria.

Which tropical fruit contains bromelain, an enzyme mix that tenderises meat and stops gelatin desserts setting?

Pineapple enzymes are degraded by cooking and canning, so tinned fruit loses the effect. Most commercial bromelain is extracted from the plant's stem.

Which 'fifth taste' did Tokyo chemist Kikunae Ikeda identify in 1908 and trace to glutamic acid?

Umami went commercial within a year: in 1909 Ikeda's patented MSG seasoning went on sale in Japan under the name Ajinomoto.

What name is given to the wave of muscle contractions that pushes swallowed food along the digestive tract?

Peristalsis squeezes behind each mouthful to stop it sliding back, then pushes it forward. Earthworms crawl using a similar rippling mechanism.

Which almond-sized region of the human brain controls hunger, thirst, sleep and body temperature?

The hypothalamus works largely through the pituitary gland, sending out hormones that switch that gland's own hormone releases on or off.

Broccoli, cabbage, kale and Brussels sprouts all belong to which vegetable family, also known as brassicas?

Crucifers are named for flowers whose four petals form a cross. Ten of the commonest, including broccoli, kale and cauliflower, are a single species, Brassica oleracea.

Which pungent kitchen staple releases the sulphur compound allicin only when it is chopped or crushed?

Garlic makes allicin as a defence against pests: crushing a clove lets an enzyme turn a stored compound into the oily liquid behind the smell.

Which breakfast grain may carry an FDA heart-health claim because its beta-glucan fibre lowers blood cholesterol?

Oats won the claim in 1997 after the FDA reviewed 33 clinical studies. It applies to at least 3 grams of beta-glucan a day.

Which gelling fibre, extracted commercially from citrus peel, makes jams and jellies set?

Pectin makes up about 30% of citrus peel but only around 1% of an apple. Soft fruits such as cherries and grapes contain much smaller amounts.

Which sweetener in sugar-free gum, sometimes called birch sugar, is poisonous to dogs?

Xylitol makes a dog's body release a surge of insulin, so its blood sugar can crash within 30 to 60 minutes of eating it.

Which bitter compound in chocolate do dogs and cats break down so slowly that it can poison them?

Theobromine is named after the cacao genus Theobroma, Greek for 'food of the gods'. Despite the name, it contains no bromine.

Which spread did Hippolyte Mège-Mouriès invent from beef tallow in 1869 to meet a challenge from Napoleon III?

Margarine was patented as 'oleomargarine' and meant for the armed forces and the poor. Despite the emperor's backing, its inventor had little commercial success.

Which UN agency, the world's largest humanitarian organisation, won the 2020 Nobel Peace Prize?

The WFP, or World Food Programme, was founded in 1961 and is based in Rome. It is also the world's leading provider of school meals.

What is the name of the antibody-rich first milk that a mother produces in the days after giving birth?

Colostrum protects a newborn against infection, and its mild laxative effect helps the baby pass its first stool.

Which seed became the ninth 'major allergen' on US food labels under the FASTER Act of 2021?

Sesame labelling backfired at first: some large bakers, unable to guarantee their products were free of the seed, began adding it to their recipes.

Which hormone, the opposite number of insulin, tells the liver to release its stored sugar when blood levels fall?

Glucagon is considered the body's main catabolic hormone. An injectable form is part of first aid for people left unconscious by low blood sugar.

What name, from the Latin for magpie, is given to persistent cravings for soil, soap, paint or other non-foods?

Pica is most commonly seen in pregnant women and small children. The magpie it is named after had a folklore reputation for eating whatever it found.

Which process, patented by Wilhelm Normann in 1902, turns liquid vegetable oils solid for use in spreads?

Hydrogenation gave cooks Crisco in 1911, the first shortening made entirely of vegetable oil. The brand name is a play on 'crystallized cottonseed oil'.

Which American author summed up healthy eating in seven words: 'Eat food. Not too much. Mostly plants'?

Michael Pollan wrote the line in In Defense of Food, which argues that 'nutritionism' has overcomplicated and harmed American eating habits.

Which compound makes rhubarb leaves poisonous and is also found at high levels in spinach and sorrel?

Oxalic acid takes its name from Oxalis, the wood-sorrel plants from which chemists first isolated it in the 1700s.

Which calorie-free fat substitute, used in Frito-Lay's WOW chips, launched with an FDA-required warning label?

Olestra can cause abdominal cramping and loose stools if eaten to excess. The FDA later dropped the label, and the chips were renamed Lay's Light in 2004.

Which compound in the skin of red grapes is sold as a supplement despite no good evidence that it extends life?

Resveratrol does so little that, by one estimate, drinking red wine to get it causes 100,000 cancers for each one it might prevent.

Which pigments colour blueberries, raspberries and some autumn leaves, appearing red or blue depending on pH?

Anthocyanins can look red, pink, purple, blue or black as acidity changes. The European Union approves them as a food and drink colouring.

Before 'vegetarian' caught on in the 1840s, English speakers named meat-free eaters after which Greek thinker?

Pythagoras lent his name to 'Pythagoreans' until the Vegetarian Society, founded at Ramsgate in Kent in 1847, popularised the modern word.

Which French chemist shut a guinea pig in an ice calorimeter to show that breathing is a slow form of burning?

Lavoisier ran the experiment with Pierre-Simon Laplace in the winter of 1782–83. They concluded that this slow combustion is what keeps an animal's body warm.

Hungarian Nobel laureate Albert Szent-Györgyi used which spice as a source of ascorbic acid in his experiments?

Paprika supplied the vitamin for experiments at the University of Szeged, and the research earned him the 1937 Nobel Prize in Physiology or Medicine.