100 free Health and Wellness trivia questions with answers — science & nature quiz, new questions added Aug 2026.
52 free Health and Wellness trivia questions with answers. How much of what you know about being healthy is actually true? This wellness quiz sorts the science from the folklore: the 10,000-steps target that began as a Japanese pedometer ad, the eight-glasses-of-water rule nobody can source, the doctor who cracked the knuckles of one hand for fifty years to see what would happen, and the World Health Organization's real numbers on sugar, salt, sleep and exercise. It is built for corporate wellness weeks, HR icebreakers, health-fair booths, nursing and PE classrooms and anyone who likes an argument about coffee. Questions cover nutrition (vitamins, fibre, trans fats, the Mediterranean diet), sleep (REM, the 90-minute cycle, melatonin, the perfect nap length), movement (WHO activity guidelines, BMI's odd origins), stress (cortisol, meditation), skin and hygiene (what SPF actually means, why 20 seconds of handwashing), and longevity (blue zones). Roughly a third are easy warm-ups; the rest will catch out people who read health headlines but not the studies. Every answer is checked against WHO fact sheets, CDC guidance or the relevant Wikipedia entry, and the source line sits under each question so nobody has to take our word for it.
30 of 100 questions with answers and explanations. Play the quiz
Q 01The famous "10,000 steps a day" target originated where?
A Japanese pedometer marketing campaign
The manpokei, or "ten-thousand step meter", was developed by clockmaker Yamasa in the run-up to the 1964 Tokyo Olympics.
Q 02Per Wikipedia, most of daily walking's health benefit arrives by about how many steps?
7,000
Thirty minutes of moderate walking works out to about 3,000-4,000 steps on a pedometer.
Q 03How many minutes of moderate aerobic activity per week does the WHO recommend for adults at minimum?
150
The vigorous-intensity equivalent is 75 minutes, and muscle-strengthening on two or more days a week is recommended on top.
Q 04In 2024, roughly what share of adults worldwide did not meet recommended activity levels?
31%
Adolescents fared far worse, at around 80 percent falling short.
Q 05How many hours of sleep per night does the National Sleep Foundation recommend for adults aged 18 to 64?
7 to 9
Newborns are advised 14 to 17 hours; over-65s 7 to 8.
Q 06A full cycle of non-REM and REM sleep takes, on average, how long?
About 90 minutes
It repeats four to six times a night, with more deep sleep early and more REM towards morning.
Q 07REM sleep is nicknamed what, since the brain acts awake while the body is paralysed?
Paradoxical
Rapid eye movement was defined and linked to dreaming in 1953 by Nathaniel Kleitman and his student Eugene Aserinsky.
Q 08Which hormone, secreted by the pineal gland at night, regulates the sleep-wake cycle?
Melatonin
It was isolated in 1958 from cow pineal glands by a dermatologist looking for something that lightened frog skin.
Q 09The word "circadian" comes from Latin words meaning what?
About a day
A rhythm only counts as circadian if it persists without external cues; in 1729 a French scientist showed a mimosa plant kept opening and closing its leaves in constant darkness.
Q 10How long does a "power nap" typically last?
10 to 30 min
NASA research found a 26-minute nap boosted pilots' alertness by 54 percent and performance by 34 percent.
Q 11NASA research found that a nap of what precise length improved pilot alertness by 54 percent?
26 min
Naps of 30 to 60 minutes tip into slow-wave sleep and risk grogginess, known as sleep inertia, on waking.
Q 12In healthy adults, caffeine's half-life is roughly how long?
3 to 7 hours
It roughly doubles in women taking oral contraceptives and drops 30 to 50 percent in male smokers.
Q 13Caffeine keeps you awake by blocking receptors for which sleep-promoting molecule?
Adenosine
It is described as the most commonly consumed psychoactive substance in the world.
Q 21Drinking far too much water can dilute blood sodium into a dangerous condition called what?
Hyponatremia
A US Army study led to a recommendation of no more than 1 to 1.5 litres per hour of heavy sweating.
Q 22Which of these can humans NOT make themselves, because the gene for the final enzyme is broken?
Vitamin C
Guinea pigs and most bats share the defect, which is why guinea pigs became the classic scurvy lab animal.
Q 23Which naval surgeon showed in 1747 that citrus fruit treats scurvy, in an early controlled clinical trial?
James Lind
He tested cider, vitriol, vinegar, seawater and a garlic-mustard paste against oranges and lemons; scurvy killed more British sailors than enemy action that century.
Q 14Health Canada advises healthy adults to consume no more than how much caffeine per day?
400 mg
A 2017 systematic review of caffeine toxicology found that limit to be safe.
Q 15The WHO says free sugars should make up less than what share of total daily energy intake?
10%
That is about 12 level teaspoons a day; going below 5 percent, the WHO adds, may bring further benefits.
Q 16According to the WHO, adults should limit salt to less than how many grams a day?
5 g
Five grams of salt is about a teaspoon and equates to 2 grams of sodium.
Q 17How many grams of fruit and veg a day does the WHO set as the floor for everyone over 10?
400 g
That figure is the origin of the familiar "five a day" of roughly 80-gram portions.
Q 18According to the WHO, no more than what share of total energy should come from trans fat?
1%
Saturated fat's ceiling is 10 percent; the WHO set a goal of eliminating industrially produced trans fat entirely by the end of 2023 and missed it.
Q 19From June 2018, the US banned which main industrial source of trans fat from food?
Partially hydrogenated oils
The FDA had ruled in 2015 that partially hydrogenated oils were not generally recognised as safe.
Q 20The advice to drink eight glasses of water a day is described on Wikipedia as what?
Not scientific
US Adequate Intake figures for total water are around 4 litres for men and 3 for women, but they assume about 20 percent comes from food.
Q 24Which 'vitamin' is technically a misnomer, being a secosteroid hormone the skin makes from sunlight?
Vitamin D
For most people skin synthesis under UVB light contributes more than diet; US milk is fortified with it.
Q 25Which nutrient is a coordination complex built around an atom of cobalt?
Vitamin B12
Hence its other name, cobalamin; deficiency in older adults is linked to dementia.
Q 26Which omega-3 must come from the diet because animals cannot make it, later converting some into EPA and DHA?
ALA
The phrase "essential fatty acids" was coined by George and Mildred Burr in 1929.
Q 27Which nutrient is defined as the part of plant food that human digestive enzymes cannot fully break down?
Dietary fibre
It comes in soluble and insoluble forms; crude corn bran is about 79 percent fibre by weight.
Q 28Who first proposed the "Mediterranean diet" concept in 1975?
Ancel and Margaret Keys
UNESCO listed the Mediterranean diet as Intangible Cultural Heritage of Humanity in 2010.
Q 29Which scientist coined the term 'body mass index' in a 1972 paper?
Ancel Keys
The underlying ratio was devised in the 1830s by Belgian astronomer Adolphe Quetelet, who never meant it as a medical tool.
Q 30A BMI of 30 or more lands you in which category?
Obese
Overweight runs from 25 to 29.9 and underweight is anything under 18.5.