Some people might be naturally blessed with pearly whites, but many people aren’t happy with the shade of their teeth. There’s nothing inherently unhealthy about yellower teeth, and staining happens throughout our lives. Norman and Tegan unpack the long history of teeth whitening (with everything from urine to nitric acid) and discuss where there’s potential for harm. References: From Gunpowder to Teeth Whitener: The Science Behind Historic Uses of Urine Shades of white: what you should know abo...
Jul 01, 2025•19 min
Coffee has been an important part of human cultures for centuries, and it has a long history of being both heralded and demonised. But the more we learn about coffee – even independent from caffeine – the more that comes to light about its potential benefits. Norman and Tegan drink in the evidence so far, which gets down to the nitty gritty of brewing techniques and milk additions. References: Coffee - The Nutrition Source - Harvard School of Public Health Coffee consumption and risk of endometr...
Jun 24, 2025•19 min
There tend to be more bugs around in winter making everyone snotty and uncomfortable. But does this mean that cold weather causes colds? Well no, viruses cause the common cold. But, as Norman and Tegan explain, winter does set the stage for those viruses to have more moments in the spotlight. References: Understanding the symptoms of the common cold and influenza - PMC Cold temperature and low humidity are associated with increased occurrence of respiratory tract infections - ScienceDirect Immun...
Jun 17, 2025•21 min
Organic fruits and vegetables are one thing, but the label is popping up on packaged foods too. Are they healthier for us because they’re certified organic? How much harm are pesticides doing to our health? Norman and Tegan dig into organic farming to find out whether they’re worth the extra price. References: Organic Certification Explained Pesticides | Food Standards Australia New Zealand Pesticides impacts on human health and the environment with their mechanisms of action and possible counte...
Jun 10, 2025•19 min
What is silence, anyway? Well if you’ve got tinnitus silence can feel like a distant dream. There are many causes of the ringing or buzzing that many people hear despite there being no external sound. Norman and Tegan discuss some of the treatments – current and in the works – that could one day bring some peace and quiet. References: Intrinsic network activity in tinnitus investigated using functional MRI Auditory Resting-State Network Connectivity in Tinnitus: A Functional MRI Study | PLOS One...
Jun 03, 2025•21 min
If you're a keen gym-goer you might've heard conflicting advice about optimising your workout. Some people claim that doing both cardio (getting your heart pumping) and strength (getting those muscles pumping) on the same day might cancel out the benefits. Norman and Tegan unpack what concurrent training is, and what the evidence tells us about its effects. References A Brief Review on Concurrent Training: From Laboratory to the Field - PMC Concurrent Training: A Meta-Analysis Examining Interfer...
May 27, 2025•18 min
Are you constantly getting scolded for pressing your cold feet against your partner in bed? Or told your hands are icy cold? It’s well known that some people run cold and others run hot. But why does this happen, and does it say anything about your health? Norman and Tegan unpack the physiology and get into some of the reasons we experience temperature differently. References: Individual differences in normal body temperature: longitudinal big data analysis of patient records | The BMJ Gender Ma...
May 20, 2025•20 min
You might've heard a friend complaining about their latest break-out and swearing off dairy products as a result. Or that friend might be you. It’s a common complaint, but does it have any scientific merit? Norman and Tegan explore whether consuming dairy can cause acne, and if so, how a glass of milk might lead to pimples. References: The Influence of Genetics and Environmental Factors in the Pathogenesis of Acne: A Twin Study of Acne in Women Patient Perceptions About Acne, Nutrition, and a Di...
May 13, 2025•20 min
You might’ve been told by parents, teachers, colleagues, friends of friends to stop cracking your knuckles because it will give you arthritis. There’s a surprising amount of science going on when you crack a joint, and it suggests there’s very little risk of harming your bones. But as Norman and Tegan explain, there is one major risk – you could irritate everybody around you. References: Mathematical Model for the Sounds Produced by Knuckle Cracking | Scientific Reports Does knuckle cracking lea...
May 06, 2025•13 min
When weighing up the health risks of getting a tattoo, most people are concerned about the risk infection. But recently the ingredients in tattoo ink have come under the microscope, with some being identified as potential carcinogens. Norman and Tegan take a look at the many substances used to create permanent art, and whether they carry any real harm to humans. References: Why Tattoos Stay Put | UCSF Synapse What's in my ink: an analysis of commercial tattoo ink on the US market - PMC Much ‘tat...
Apr 29, 2025•20 min
The carnivore diet asks people to eat entirely animal-based, and the most extreme followers restrict themselves to only meat. Many carnivores claims they feel great — better than they ever have. They have more energy and lose weight. Norman and Tegan tuck into the reasons why carnivores feel better in the short-term, and the dangers they're inviting in the long-term. References: Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a “Carnivore Diet” - Current De...
Apr 22, 2025•22 min
Hot flashes. Night sweats. Aching joints. Sore boobs. Welcome to your body in perimenopause! In episode one of this four-part series, Yumi Stynes speaks to women in the thick of perimenopause and battling physical symptoms. She also sits down with Dr Susan Davis, endocrinologist and world-leading expert on sex hormones and ageing to learn the best treatments for bothersome symptoms and how look after yourself in this stage of life. No sweat! Essential listening if you're going through perimenopa...
Apr 17, 2025•31 min
Do you find yourself complaining that you've got a small bladder, as you run to the toilet for the third time in an hour? There are many reasons a person might pee more than others, including some scary medical conditions. But as Norman and Tegan explain, in most cases your bladder is just deconditioned and you need to get your urinary tract into shape. References: Bladder control: Lifestyle strategies ease problems A randomized double-blind placebo-controlled clinical trial of a product contain...
Apr 15, 2025•18 min
Microplastics are everywhere – they’re in the air, in the water and in our bodies. There’s plenty of evidence for that, but it’s still unclear what effects these microplastics are having on our health. Norman and Tegan unpack what we do and don’t know about these tiny specs of plastic, and what you might be able to do about them. References: Ingested microplastics: Do humans eat one credit card per week? A review of the endocrine disrupting effects of micro and nano plastic and their associated ...
Apr 08, 2025•21 min
This week parts of Australia are preparing to wind back their clocks to mark the ending of daylight saving time. For a long time the country has been divided about the positives and the negatives of changing the clocks twice a year. Norman and Tegan look into the health effects of this shift – from the impact on sleep to medical procedures and road accidents. References: Basic concepts and unique features of human circadian rhythms: implications for human health | Nutrition Reviews | Oxford Acad...
Apr 01, 2025•20 min
If you're short-sighted or long-sighted, have astigmatism or double vision, you now live in a world where glasses can help you out. But there's a misconception hanging around that wearing spectacles weakens your eyes over time, and so some people avoid getting their vision checked. Norman and Tegan focus in on how glasses work and the long term impacts of wearing them. References: When time outside doesn't slow short-sightedness - the Health Report The history of spectacles - the College of Opto...
Mar 25, 2025•19 min
We haven’t always suppressed our sweat or our natural body odour, but in many cultures now it’s expected we’ll all try to smell our best. You might be seeing more ads for ‘natural’ deodorants that promise to keep you fresh without any harmful ingredients. Norman and Tegan talk through those ingredients, and whether they carry any risks. References: The specific biochemistry of human axilla odour formation viewed in an evolutionary context Use of Aluminium in Antiperspirants - Australian Departme...
Mar 18, 2025•19 min
Protein is having its moment — walk any supermarket aisle and you'll find product after product boasting its protein content. Do you need to be loading up on protein through powders or processed foods, or can you meet your goals with whole foods? Norman and Tegan unpack why protein is important and how much you need each day. References: Protein - Nutrient Reference Values for Australia and New Zealand Tips to boost protein in your diet from Dietitians Australia How much protein can the body use...
Mar 11, 2025•17 min
Long-time listeners would have heard Norman decrying fine particulate air pollution and its negative effects on health. But when it’s all around us – on our worksites, in our offices and on our motorways – how are you supposed to protect yourself? Norman and Tegan explain what fine particulate air pollution is, and what it does to the body once it’s breathed in. References: Estimates of global mortality burden associated with short-term exposure to fine particulate matter (PM2.5) The health effe...
Mar 04, 2025•20 min
Cramping muscles are common, whether they’re associated with exercise or not. Knowing what causes them can help people avoid them or treat them, but for many people it's not a simple story. Norman and Tegan talk through some of the theories behind this painful phenomenon, and why magnesium might not be the answer. References: Muscle cramps: A comparison of the two-leading hypothesis Influence of Hydration and Electrolyte Supplementation on Incidence and Time to Onset of Exercise-Associated Muscl...
Feb 25, 2025•19 min
Hair loss is common, but there are many different causes and potentially many different treatments. From topical ointments to light therapy, to scalp massage routines. What works to slow, or even reverse, hair loss? Norman and Tegan comb through the evidence for approved treatments and too-good-to-be-true snake oil. References: Male pattern baldness - Healthdirect Male Androgenetic Alopecia with an overview of treatments - NIH Female pattern hair loss - Healthdirect What is minoxidil, the anti-b...
Feb 18, 2025•18 min
What's That Rash? is returning to the World Science Festival Brisbane for another year. Norman and Tegan will be answering the health questions everyone (at WSFB) is asking, 10am on March 30 at Queensland Museum Theatre. Check out the event here and send in your questions to [email protected]
Feb 17, 2025•1 min
The use of mushrooms in medicine goes back centuries, but there’s still a lot to learn about the bioactive compounds in fungi. There are many claims surrounding 'functional mushrooms' – types of mushrooms thought to have medicinal properties beyond simple nutrition. These include lion’s mane, reishi, cordyceps, shiitake and turkey tail. Norman and Tegan forage through the evidence for using mushrooms against cancer, to boost the immune system and to amplify cognition. We're doing a live show! Ca...
Feb 11, 2025•20 min
Depending on your corner of the internet, you might have seen people swearing by this new sleep hack, mouth taping. People claim they’re better rested, have better breath and stronger jawlines – all because they force themselves to breathe through their noses overnight. Norman and Tegan tackle this taping trend with an N=1 experiment, and a look at the relevant research. References: Mouth taping: a little less conversation, a little more action, please! Effect of mouth taping at night on asthma ...
Feb 04, 2025•18 min
Unfortunately many more people have heard about brain fog because of the pandemic and long COVID. But the symptom was first mentioned centuries ago, and has been associated with dozens of conditions. Norman and Tegan try to define brain fog, and explain why it can be difficult to treat. References: What is brain fog? - BMJ neuropsychiatry Subjective brain fog: a four-dimensional characterization in 25,796 participants Comprehensive Clinical Characterisation of Brain Fog in Adults Reporting Long ...
Jan 28, 2025•15 min
It can be hard to keep up with food fads and diet trends (and spoiler: you don’t need to). But an intriguing assumption that has gained traction recently is that seed oils – think canola, sunflower, grapeseed – are terrible for you. Norman and Tegan unpack how that assumption has spread, and whether there’s any solid evidence to back it up. References: Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality Serum n-6 polyunsaturated fatty acids and risk of dea...
Jan 21, 2025•19 min
January is an especially sweaty time in Australia, so maybe park this life change until the weather cools down… But is it necessary to bathe every day? As we learn more about the microbiome on our skin, more and more people are questioning their hygiene routine. Norman and Tegan sniff out the evidence for and against regular washing. References: A natural history of hygiene The Cutaneous Microbiome and Aspects of Skin Antimicrobial Defense System Resist Acute Treatment with Topical Skin Cleanser...
Jan 14, 2025•17 min
You might've heard of the blood type diet popularised in the 90s off the back of a best-selling book. It’s based on the theory that blood types emerged at different times in history, when our ancestors had very different diets. So does that mean certain foods are better for an A-, an AB+ or even an O-?As Norman and Tegan explain, it’s a complicated story. References: Blood type diets lack supporting evidence: a systematic review Blood Type Is Not Associated with Changes in Cardiometabolic Outcom...
Jan 07, 2025•18 min
There are MANY books out there on habit formation. Are they all saying the same thing? Some habits are more complicated than others. Some habits require us to untangle one automatic set of behaviours and replace them with another. It can be a long process — much longer than the 21 days that's often promised. Norman and Tegan tell us how to form a new habit, in far less than 300 pages, so you can get started. References Neurobiology of habit formation How the brain controls our habits - MIT Bridg...
Dec 31, 2024•19 min
'Tis the season to indulge. As you sit down with family and friends, an age-old debate might arise: does drinking a single glass of red wine make you healthier? In this episode first published May 1, 2024, Norman and Tegan try to find out the answer once and for all. References: The French paradox: Lessons for other countries Moderate Wine Consumption and Health: A Narrative Review Health Effects of Red Wine Consumption: A Narrative Review of an Issue That Still Deserves Debate...
Dec 24, 2024•14 min
