Ask the Naked Scientists

Fizzy drinks after a long run?

12 Dec 2025

Contributed by Lukas

Today, Chris Smith tackles a whole host of health-related questions. We explore the impact of a meat-based diet, whether it's a good idea to drink fiz...

Can our eyes pop out when we sneeze?

05 Dec 2025

Contributed by Lukas

This week, Chris Smith and Clarence Ford tackle the big science questions of the week, including how to perform a circumcision safely; can our eyes po...

Why do dogs make a beeline for underwear and smelly socks?

28 Nov 2025

Contributed by Lukas

Why do dogs make a beeline for underwear and smelly socks? Also, do we really get taller at night, why do some colours reflect and others absorb light...

Are zebras black with white stripes?

21 Nov 2025

Contributed by Lukas

Are any people particularly susceptible to alopecia-linked hair loss? Also, what causes eczema and why does it keep recurring, why are the progeny of ...

Will we find a cure for diabetes?

14 Nov 2025

Contributed by Lukas

In Ask! the Naked Scientists, Dr Chris Smith answers listeners' medical questions. This time, what causes a black eye? How can we alleviate the pain f...

Is an elephant really related to a hyrax?

07 Nov 2025

Contributed by Lukas

Is an elephant really a close relative of a hyrax? What are blood groups? Is there really such a thing as a selfish gene? How did males and females ev...

Are some people missing an arm muscle?

31 Oct 2025

Contributed by Lukas

Are some people missing arm muscles? Are there other muscles that we're losing? Can bats and moles actually see? Can the side effects of prostate surg...

Are satellites safe from terrorist attacks?

24 Oct 2025

Contributed by Lukas

What happens to helium balloons that float away? Are satellites safe from terrorist attacks? Why does the truth hurt? Why does some poo float after fl...

For a short time, I forgot who I was. What happened?

17 Oct 2025

Contributed by Lukas

Why does La Nina cause more rainfall in South Africa? How can we keep our skin moist without buying products? Is it possible to be averse to iron in y...

Are women really more nurturing?

10 Oct 2025

Contributed by Lukas

It's another jam-packed episode of Ask the Naked Scientist, illuminating listener questions - in all their usual, rich variety - with fascinating scie...

How is it possible to have 2 different eye colours?

03 Oct 2025

Contributed by Lukas

In this episode of Ask the Naked Scientist: is it possible to teleport atoms? Does garlic repel mosquitoes? What is vaginal thrush? Like this podcast?...

Can spicy food make your ear itch?

26 Sep 2025

Contributed by Lukas

In today's episode of Ask! Dr Chris answers: why do some people attract more mosquitoes than others? Is there a link between sweating and sour tastes?...

Why do my wife's eyes light up when she sees me?

19 Sep 2025

Contributed by Lukas

In this episode of Ask, if the universe is expanding, what's it expanding into? What's the relationship between descended testes and the chance of hav...

Why do we dislike the sound of our own voices?

12 Sep 2025

Contributed by Lukas

On Ask! the Naked Scientist this week: What led to the 'leopard spots' found on Mars? What is the purpose of finger and toe nails? How do bone conduct...

How can you control your phobias?

05 Sep 2025

Contributed by Lukas

Is it dangerous to have floaters in your eye? Can you power a lamp with your mouth? Are nations in the global north more innovative than nations in th...

Why does sex make you sleepy?

29 Aug 2025

Contributed by Lukas

Is the flipping of Earth's magnetic field a concern? Why might half-filled ice cube trays freeze faster? Why does sex make you sleepy? Why might you g...

Are there fragments of insects in chocolate?

22 Aug 2025

Contributed by Lukas

Dr Chris answers listener questions including: do men and women have an equal chance of getting sports injuries? What health benefits can a sugar free...

Why is it so important to finish a course of antibiotics?

15 Aug 2025

Contributed by Lukas

Dr Chris is back to answer listener questions. Why do cat's eyes reflect bright colours? What are the short, high pitched ringing noises that can some...

Do animals feel fear?

01 Aug 2025

Contributed by Lukas

Do animals feel fear the same way that we do? Do diet supplements boost your immune systems? Can using phones and headphones change the shape of your ...

Will our universe keep on growing?

25 Jul 2025

Contributed by Lukas

Dr Chris takes on more listener questions. Including: is Chinese medicine separate from Western medicine? Why do we sometimes cry in response to feeli...

Why do adults take longer to wake up than babies?

18 Jul 2025

Contributed by Lukas

The questions keep coming for Dr Chris. This week they include: have scientists got their hands on the oldest ice ever studied? Does putting the air c...

Why do medicines get discontinued?

11 Jul 2025

Contributed by Lukas

In this episode of Ask! Dr Chris is asked: what is ivermectin? Are sodium ion batteries a rival to lithium? Is the Earth spinning slightly faster? Why...

Is leukaemia genetic?

04 Jul 2025

Contributed by Lukas

Do we have another comet visiting from outside the solar system? What is Oumuamua? Is the Ring of Fire amping up in activity? Is leukaemia genetic? Do...

Why does cold water take your breath away?

27 Jun 2025

Contributed by Lukas

Why does cold water take your breath away? And why is it cold when you leave the cold water? What smells does an ant produce? Is there a psychological...

Why can't you tickle yourself?

20 Jun 2025

Contributed by Lukas

Dr Chris answers listener questions including: what is the Higgs boson? How should I change my lifestyle to prevent diabetes? Why can you pass on yawn...

Naked Scientists SOS

16 Jun 2025

Contributed by Lukas

Cambridge University have informed us that, for cost cutting reasons, they intend to make Dr Chris Smith redundant. Naturally, this jeopardises the Na...

Why does bleach claim to kill 99.9% of bacteria?

13 Jun 2025

Contributed by Lukas

Chris Smith answers listener science questions. They include, is it worth getting the flu vaccine? Is COVID still around? Is it possible to manufactur...

Would a compass work on the Moon?

06 Jun 2025

Contributed by Lukas

Dr Chris with more answers to listener science questions: why was the discovery of the Higgs boson worthy of a Nobel Prize? Are birth rates falling ar...

Can a person be cloned?

30 May 2025

Contributed by Lukas

Dr Chris answers listener questions including, how effective is the flu shot? Is there anything doctors don't want their patients to know? Do our eyes...

When did life start evolving sex?

23 May 2025

Contributed by Lukas

Dr Chris answers questions on CapeTalk, including: how often should we wash our clothes? Is there a relationship between the Earth's gravity and magne...

What determines the speed of your internet?

16 May 2025

Contributed by Lukas

Why is February only 28 days long? Is there a link between red meat, testosterone, and male violence? Is there a 'best' LLM? Can macular degeneration ...

Should dogs sleep inside the house?

09 May 2025

Contributed by Lukas

Ask! The Naked Scientist covers questions including, are we humans the universe's consciousness? Is the presence of dimethyl sulphide on an exoplanet ...

Are gravity and magnetism related?

02 May 2025

Contributed by Lukas

In this week's Ask!, Dr Chris explains what we know about deja vu (have we had this one before?) Also, what might have been behind the major power out...

Does the shingles vaccine reduce risk of dementia?

25 Apr 2025

Contributed by Lukas

Are there signs of life on another planet? Could a shingles vaccine prevent dementia? Do artificial sweeteners increase our appetite? How is obesity m...

Are girls better at maths than boys?

18 Apr 2025

Contributed by Lukas

In Ask! the Naked Scientist, Dr Chris answers medical enquiries such as: why a pacemaker may cause some discomfort. Why might you get a migraine if yo...

Are seed oils unhealthy?

11 Apr 2025

Contributed by Lukas

In this week's Ask the Naked Scientist, Chris Smith tells us if we are seeing an increase in cancer numbers. Also, what are the underlying causes of c...

Is my microwave disrupting my Wi-Fi?

04 Apr 2025

Contributed by Lukas

In this episode of Ask the Naked Scientist: does miso ferment differently in space? How can I improve my memory? Could receiving hepatitis A, tetanus,...

Does food taste different on an aeroplane?

28 Mar 2025

Contributed by Lukas

Why do we have different blood groups? What drives the libido? Do you get drunk faster on an aeroplane? How long does an artificial heart valve last? ...

Can aspirin help prevent cancer?

21 Mar 2025

Contributed by Lukas

In this episode of Ask! Dr Chris answers questions including: what are the minerals in mineral water? Is it safe to drink water from plastic bottles? ...

Do edibles hit you harder than smoking a joint?

14 Mar 2025

Contributed by Lukas

On Ask! the Naked Scientist, Can you keep sparkling water fizzy for longer? Are magnesium tablets good for us? Why do we crave certain foods? How do b...

Can one black hole swallow another?

07 Mar 2025

Contributed by Lukas

Is everywhere at the centre of the universe? How long do sweeteners stay in the digestive system, and what are the best alternatives? Can one black ho...

Why is a dog's nose always wet?

03 Mar 2025

Contributed by Lukas

Dr Chris answers science questions from listeners to TalkRadio 702, including; How does one improve short term memory, especially following a brain in...

Is AI polluting medical literature?

21 Feb 2025

Contributed by Lukas

Dr Chris answers the usual spectrum of science questions from listeners to CapeTalk, including; are sweeteners bad for our cardiovascular health? If a...

Could a falling bullet injure you?

14 Feb 2025

Contributed by Lukas

Do atoms carry memory of information? What happens when dopamine circuits are interrupted? Why might you hiccup when you shave? Why do both kidneys fa...

Why do dogs age faster than humans?

07 Feb 2025

Contributed by Lukas

In this episode of Ask! Dr Chris tells us what causes humiditiy in the air. Why are carbonated drinks bad for your teeth? Does the Naked Scientist kno...

Why are humans the only species with advanced intelligence?

31 Jan 2025

Contributed by Lukas

Dr Chris answers more listener questions, including: How do sunflowers follow the sun? How does the body determine when you're passing wind or somethi...

How do plants know which way is up?

24 Jan 2025

Contributed by Lukas

How can you use sticks to calculate the circumference of the Earth? Can exfoliators remove your fingerprints? How do plants know which way is up? What...

What causes ulcers?

17 Jan 2025

Contributed by Lukas

Why do ants drown themselves? Could we power cars with electrolytes? What causes ulcers? Do metal wrist rings actually reduce pain? Should you take pr...

How do you find black holes?

10 Jan 2025

Contributed by Lukas

Should you try to break bad habits? How do you stop a 'wandering' itch? Does climate change affect rainfall? Will you be tired if you dream of being a...

Why should you cook at different temperatures in fan ovens?

20 Dec 2024

Contributed by Lukas

Dr Chris takes on the final batch of questions of 2024 on CapeTalk. Why does sound cause me pain? What's the difference between white and brown vinega...

What colour should I paint my garage roof?

06 Dec 2024

Contributed by Lukas

Chris Smith answers CapeTalk listeners' questions. Including, do wind turbines affect the temperature of the ground? What is the cause of protein buil...

Why does toothpaste contain fluoride?

29 Nov 2024

Contributed by Lukas

Dr Chris Smith takes on listener questions on South Africa's CapeTalk. Why is there a delay between live TV and radio? Do wind turbines warm the air a...

Why is sunlight so important for the body?

22 Nov 2024

Contributed by Lukas

Why are we called The Naked Scientists? Why should you get sunlight in the morning? Why does bright light make you sneeze? Does luck have a pattern? I...

Has it been a strange year for weather?

15 Nov 2024

Contributed by Lukas

Dr Chris Smith answers questions from the listeners of CapeTalk. Including, why are pregnant women told to take folic acid? What causes ears to itch? ...

Why do athletes spit on the ground?

08 Nov 2024

Contributed by Lukas

Dr Chris and Clarence take on another selection of topics from across the scientific spectrum: Who were the victims of the Mount Vesuvius eruption? Ho...

What should you do if a lift cable snaps?

01 Nov 2024

Contributed by Lukas

Do animals lower their mating standards when drunk? Why do different farts make different noises? What should you do if your lift cable snaps? Were th...

Do other animals see colour?

25 Oct 2024

Contributed by Lukas

In this episode of Ask! The Naked Scientist, Dr Chris explains how our eyesight changes as we age, what the difference is between a brown and white eg...

Are ambidextrous people more intelligent?

18 Oct 2024

Contributed by Lukas

Listener science questions from South Africa answered by Dr Chris this time include: Do you urinate more liquid than the alcohol you consume? Why do d...

Why do we have car headlights on during the day?

11 Oct 2024

Contributed by Lukas

Dr Chris answers listener questions. Including, is air made up of the same proportion of stuff everywhere on Earth? What is earwax? Where is it produc...

What is the best way to get rid of hiccups?

04 Oct 2024

Contributed by Lukas

Can you bring someone back from the dead? Can a special diet help flexibility in older people? What is the best way to get rid of hiccups? Are hovercr...

Why do fairground rides get worse as we age?

27 Sep 2024

Contributed by Lukas

In a break from the usual format, the producers of The Naked Scientists take over from Clarence Ford to ask Dr Chris Smith some of your burning scient...

Should you wash every day?

20 Sep 2024

Contributed by Lukas

Should you wash every day? Does washing your clothes damage them? Should you have a washcloth just for your face? Why does moving air make the tempera...

Are more male babies born after a war?

13 Sep 2024

Contributed by Lukas

Why do some people struggle to read? Are more male babies born after a war? Are some people allergic to hot skin? Why do some men's breasts swell up? ...

Can someone's heart keep beating after death?

06 Sep 2024

Contributed by Lukas

Why do some people grind their teeth? Can someone's heart keeping beating when they're dead? How does the brain interpret words? How do we know how lo...

How do bones heal themselves?

30 Aug 2024

Contributed by Lukas

How much do wildfires contribute to carbon release? How do bones heal themselves? Why do weeds seem to grow faster than other plants? Why do some anim...

What should we know about monkeypox?

23 Aug 2024

Contributed by Lukas

What is monkeypox, and how can we tackle it? Why can't you walk through walls if atoms are mostly empty space? If X-Rays are harmful, why are microwav...

Will we ever run out of helium?

16 Aug 2024

Contributed by Lukas

Will we ever run out of helium? Will any planets in the solar system get knocked out of orbit? What causes ovulation pain? Is it wise to pop a zit? Wh...

How many cigarettes does it take to get hooked?

12 Aug 2024

Contributed by Lukas

This week, Dr Chris and Relebongile find out how dietary salt affects the body, how loneliness and loss of a loved one can cause ill-health, what a bl...

Why do athletes perform better on the day?

02 Aug 2024

Contributed by Lukas

Questions for Dr Chris Smith on this week's Ask! include: What are the health benefits of exercise? How do you explain deja vu? Can you be in two plac...

Do teabags carry microplastics?

26 Jul 2024

Contributed by Lukas

Dr Chris answers a wide range of listener science questions. What is entropy and how does it reconcile with equilibrium? What happens when they put do...

Why can't other apes grow long head hair?

19 Jul 2024

Contributed by Lukas

Why does your washing sometimes smell bad? What is the difference between forecast temperature and 'real feel'? Why can't other apes grow long head ha...

Are we overprotective of our children?

12 Jul 2024

Contributed by Lukas

Dr Chris answers listener submitted questions including: would it be possible to slingshot continuously around the Earth and Mars? When does our consc...

Why can we only recycle some types of plastic?

05 Jul 2024

Contributed by Lukas

Do women suffer from flatulence, and what affects your level of flatulence? Does hitting someone on the head actually knock them out? Is being a psych...

What happens to the body in extreme cold?

28 Jun 2024

Contributed by Lukas

Does laying on your left side clean your organs? Are faces the only difference that different populations have, and why do we notice facial difference...

Would an organ donor's DNA be in your body?

21 Jun 2024

Contributed by Lukas

What causes monkeypox? Would an organ donor's DNA be in your body? Why does alcohol abate the symptoms of a hangover? Can you get bird flu from bird p...

Why is the longest day not the hottest day?

14 Jun 2024

Contributed by Lukas

Dr Chris Smith answers listener science questions; what factors impact the onset of glycosuria? Might we have contaminated Mars with organisms from Ea...

Why don't our lungs fill up with dust?

07 Jun 2024

Contributed by Lukas

Are skin tags an indication of diabetes? Why don't cattle flee from fire? Do apples stimulate your appetite? Why are some cats great at hunting, and o...

Are some people more prone to addiction?

31 May 2024

Contributed by Lukas

Dr Chris Smith chats with Relebogile Mabotja and her listeners about their science questions. Today: do older people yawn less frequently? And should ...

How were the pyramids built?

24 May 2024

Contributed by Lukas

This time on Ask!, Dr Chris explains how tree rings helped scientists confirm last summer was the hottest for 2000 years. Also, how were the pyramids ...

Is there a cure for OCD?

17 May 2024

Contributed by Lukas

Chris Smith covers another cast of interesting queries submitted by listeners. They include: Why do we have accents? Is there such a thing as the "dev...

Do fish drink water?

10 May 2024

Contributed by Lukas

Dr Chris takes on listener questions: how long can someone survive without food and water? Why are some of us more prone to hangovers? Do gorillas dri...

Is the '10,000 hours rule' accurate?

03 May 2024

Contributed by Lukas

In this week's selection of science questions, Dr Chris explains the impact of sweetners on the body, what happens when we suffer a stroke, and where ...

How does cloud seeding work?

26 Apr 2024

Contributed by Lukas

Why are viruses so contagious? Are there any treatments for macular degeneration? How are we treating depression with psychedelics? Why do people lose...

Why do we dream the things we dream?

19 Apr 2024

Contributed by Lukas

Is our perfect total eclipse just a total coincidence? Where do our dreams come from? Can you launch a missile without it being picked up by satellite...

Are lactose intolerant mothers allergic to their own milk?

12 Apr 2024

Contributed by Lukas

Why did the eclipse move west to east across the Earth? Why are we so interested in nuclear fusion? Could we ever breathe underwater? What is the oppo...

Do ants count their steps?

05 Apr 2024

Contributed by Lukas

Do animals ever get lost? Do ants count their steps? Could we recreate the greenhouse effect on Mars? Why can you hear some aircraft, but not others? ...

Do farmers produce double yolk eggs on purpose?

22 Mar 2024

Contributed by Lukas

Dr Chris answers more listener submitted questions including, Why is South Africa on the bottom of the world map? Why are countries interested in land...

Why do we want to scratch our wounds?

15 Mar 2024

Contributed by Lukas

Chris Smith answers science questions from the public. Does the rate of nail growth differ between men and women? What are the advantages of a nose sw...

Could popping a pimple on your face kill you?

08 Mar 2024

Contributed by Lukas

Do statins affect your Vitamin D production? Why do we have leap years? Which came first, the chicken or the egg? Could we live on the moon of Titan? ...

How much does the internet weigh?

01 Mar 2024

Contributed by Lukas

Chris Smith answers another sample of enquiries from across the scientific spectrum: What might have caused my beetle infestation? Why do so many cult...

Can you die of fright?

23 Feb 2024

Contributed by Lukas

What causes the noise in a lightning strike? How do astronauts' bodies change after a long time in space? Can you die of fright? Are we living in the ...

Does your life flash before your eyes when you die?

16 Feb 2024

Contributed by Lukas

Why do birds stand on one leg? Which animals can we eat, and which can we not? Does your life flash before your eyes when you die? Does a plug's wirin...

How much rainfall becomes groundwater?

09 Feb 2024

Contributed by Lukas

Dr Chris Smith answers listener questions including, how can we communicate science better? How much distance do we travel through space each second? ...

How does the Sun transfer heat to the Earth?

02 Feb 2024

Contributed by Lukas

Chris Smith takes on listener questions, including: How far out to sea do seagulls fly? How is the malaria vaccine rollout going? Why does hot weather...

What is ultra processed food?

26 Jan 2024

Contributed by Lukas

Chris Smith takes on listener submitted questions including, why do people disagree so much on what temperature to set the heating? Where do swallows ...

Do mosquitoes prefer certain people?

19 Jan 2024

Contributed by Lukas

Why might chilli cause an upset stomach? How does a boomerang work? What's the difference between 50Hz and 60Hz of energy? Why does Saturn have a hexa...

Why doesn't the Earth make wind as it moves through space?

12 Jan 2024

Contributed by Lukas

Why kind of gas is in a gas giant planet? Can you do anything about sleepwalking? What causes stutters and speech impediments? Does blowing out birthd...

Where did Earth get its water from?

05 Jan 2024

Contributed by Lukas

In the first Ask! of 2024, Dr Chris Smith tackles questions on UV rays, Fahrenheit vs Celsius, whether the Three Gorges Dam could be slowing down the ...

Are some wildfires beneficial?

22 Dec 2023

Contributed by Lukas

Are some wildfires beneficial? What is the worst case scenario for climate change? What causes lactose intolerance? Does sunscreen cause a vitamin D d...

Does Mercury have a moon?

18 Dec 2023

Contributed by Lukas

This week, a Christmas surprise in Dr Chris's tree that he'd rather not have brought home; should I drink water from aircon machines or even vehicle e...