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. This episode first aired on March 19, 2025.  References: The specific biochemistry of human axilla odour formation viewed in an evolutionary context Use of Aluminium in Antiperspirants - Australian Department of Health Antiperspirants/Deodorants and Breast Cancer - National Cancer Institute Antiperspirants - National Kidney Foundation How Advertisers Convinced Americans They Smelled Bad - Smithsonian Magazine

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.  This episode first aired on April 15, 2025.  References: Bladder control: Lifestyle strategies ease problems A randomized double-blind placebo-controlled clinical trial of a product containing pumpkin seed extract and soy germ extract to improve overactive bladder-related voiding dysfunction and quality of life Pumpkin Seed Oil Extracted From Cucurbita maxima Improves Urinary Disorder in Human Overactive Bladder Prosta Fink Forte capsules in the treatment of benign prostatic hyperplasia. Multicentric surveillance study in 2245 patients

There have been many discussions this year about sunscreen, its effectiveness and its ingredients. While there are some unknowns, what we’re sure of is sunscreen’s ability to protect us from the sun’s ageing and cancer-causing rays. Norman and Tegan slip, slop, slap some questions about sunscreen: SPF scandal, endocrine disruptors and vitamin D concerns. References: How does sunscreen work? - Cancer Council  Sunscreen: a brief walk through history We tested the SPF claims of 20 sunscreens. 16 failed - CHOICE TGA statement on CHOICE SPF sunscreen findings  Safety Review of Seven Active Sunscreen Ingredients – July 2025  Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial Mineral vs chemical sunscreens  Can your sunscreen expire?  If you enjoyed this episode, check these out! Is there such thing as TOO much sun protection? We all need a daily dose of sunlight — but how much?  Can you get away with skipping your daily shower?

Creatine is getting a lot of hype lately, at least according to our listeners. It’s being pushed for everything from menopause to dementia for its supposed energy-boosting, brain-boosting benefits. Norman and Tegan explore what is really going on with creatine outside of its muscle-building potential. References: Common questions and misconceptions about creatine supplementation: what does the scientific evidence really show? | Journal of the International Society of Sports Nutrition  Metabolic Basis of Creatine in Health and Disease: A Bioinformatics-Assisted Review - Nutrients  Creatine in Health and Disease  Creatine supplementation for older adults: Focus on sarcopenia, osteoporosis, frailty and Cachexia Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation Creatine monohydrate pilot in Alzheimer's: Feasibility, brain creatine, and cognition  The Effects of 8-Week Creatine Hydrochloride and Creatine Ethyl Ester Supplementation on Cognition, Clinical Outcomes, and Brain Creatine Levels in Perimenopausal and Menopausal Women (CONCRET-MENOPA): A Randomized Controlled Trial  It Is Not Just About Storing Energy: The Multifaceted Role of Creatine Metabolism on Cancer Biology and Immunology Creatine Supplementation for Patients with Inflammatory Bowel Diseases: A Scientific Rationale for a Clinical Trial  International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine  If you enjoyed this episode, check these out! Is it safe to dose yourself with pre-workout? Do healthy people need lymphatic treatments? Is that glass of red wine over Christmas dinner good for you?

Whether or not we remember our dreams, we all have them. But the answer to why we dream is complicated. There's a lot going on in our brains during sleep, especially during the rapid eye movement (REM) phase when most dreams go down. Norman and Tegan talk through the purpose of dreams, how time warps as we snooze and whether there are any downsides to these nightly hallucinations. References: Dreams: Why They Happen & What They Mean – Sleep Foundation  Time for actions in lucid dreams: effects of task modality, length, and complexity  High Dream Recall Frequency is Associated with Increased Creativity and Default Mode Network Connectivity fMRI Evidence for Default Mode Network Deactivation Associated with Rapid Eye Movements in Sleep  The relationships between insomnia, nightmares, and dreams: A systematic review Nightmares affect the experience of sleep quality but not sleep architecture: an ambulatory polysomnographic study  Gender differences in dreaming: Are they stable over time? Isotretinoin use and reports of sustained dreaming | British Journal of Dermatology | Oxford Academic Dreaming under antidepressants: A systematic review on evidence in depressive patients and healthy volunteers Nightmare and Abnormal Dreams: Rare Side Effects of Metformin? If you enjoyed this episode, check these out! What's the deal with night terrors? How risky is sharing a toothbrush? Should you go organic if you're worried about pesticides?

When you’ve got a busy schedule, it’s important to just exercise when you can. But if you have the luxury of choice, is there an optimal one? You might’ve even heard that exercising at certain times of day can lead to harm. Norman and Tegan run through the evidence around heart attacks, workouts and what happens when you’re a morning or a night person. References: Association of the time of day of peak physical activity with cardiovascular mortality: Findings from the UK Biobank Study Setting your clock: associations between timing of objective physical activity and cardiovascular disease risk in the general population  Best Time of Day for Strength and Endurance Training to Improve Health and Performance? A Systematic Review with Meta-analysis  Gold, silver or bronze: circadian variation strongly affects performance in Olympic athletes Diurnal variation in tennis service The effects of exercise session timing on weight loss and components of energy balance: midwest exercise trial 2  If you enjoyed this episode, check these out! Chronotypes: early birds vs night owls Does magnesium work against muscle cramps? Norman tried an ice bath so you don't have to

Humans are slightly alkaline – your blood should be a pH between 7.35 to 7.45. Anything outside that range can be life-threatening. So why are you being told to follow an alkaline diet? Proponents of the diet claim it can tackle everything from osteoporosis to cancer. Norman and Tegan do a litmus test on the alkaline-acid balance and whether it’s a driver of chronic disease. References: Physiology, Acid Base Balance The effect of acid ash and alkaline ash foodstuffs on the acid-base equilibrium of man Urine pH is an indicator of dietary acid–base load, fruit and vegetables and meat intakes: results from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk population study Why is there so much on the internet about the alkaline diet and cancer? – MD Anderson  Low-grade metabolic acidosis as a driver of chronic disease: a 21st century public health crisis Diet-Induced Low-Grade Metabolic Acidosis and Clinical Outcomes: A Review If you enjoyed this episode, check these out! Why Norman won't shut up about the Mediterranean diet Why is the internet telling me to lower my cortisol? MSG's messy myths and racist tropes

You’re settling into the couch after a long day, ready to relax with your favourite show … next thing you know, you’re asleep. What is it about the TV that puts people to sleep, and what can you do to avoid dozing off? Norman and Tegan explore comfort watching, binge-watching and blue light exposure. References: Exploring the Bob Ross effect: A psychophysiological investigation Binge Viewing, Sleep, and the Role of Pre-Sleep Arousal | Journal of Clinical Sleep Medicine The inner clock—Blue light sets the human rhythm  Morning and Evening Blue-Enriched Light Exposure Alters Metabolic Function in Normal Weight Adults Mitigating the Effects of Blue Light - Sleep Foundation  If you enjoyed this episode, check these out! What is the perfect nap duration? Why do you feel so tired after a big meal? Is your (artificial) sweet tooth killing you?

If you've seen a physiotherapist, you might’ve undergone needling with the promise it will reduce your pain. Did you receive dry needling or acupuncture? How can you tell the difference between the two? Norman and Tegan poke through the evidence to find out how effective these techniques can be. References: Similarities between Ashi acupoints and myofascial trigger points: Exploring the relationship between body surface treatment points  Dry Needling versus Acupuncture: The Ongoing Debate Acupuncture: Past, Present, and Future  Clinical Effectiveness of Dry Needling in Patients with Musculoskeletal Pain—An Umbrella Review  Methodological challenges in design and conduct of randomised controlled trials in acupuncture  Needling Point Location Used in Sham Acupuncture for Chronic Nonspecific Low Back Pain: A Systematic Review and Network Meta-Analysis Comparison of dry needling and trigger point manual therapy in patients with neck and upper back myofascial pain syndrome: a systematic review and meta-analysis Acupuncture for Chronic Pain: Individual Patient Data Meta-analysis Acupuncture for musculoskeletal pain: A meta-analysis and meta-regression of sham-controlled randomized clinical trials Magic tricks are helping scientists understand the placebo effect and pain - ABC News If you enjoyed this episode, check these out! Can you zap yourself buff with electrical muscle stimulation? Are office jobs ruining our bodies? Is gluten really the enemy?

You might’ve seen headlines about high levels of lead being found in common protein supplements. With these products becoming more popular, the news has some eager gym-goers concerned about what they’re consuming. Norman and Tegan discuss how these results compare to our historical exposure – from Ancient Rome to Australia in the 1960s. References: Protein Powders and Shakes Contain High Levels of Lead - Consumer Reports Bioaccumulation of lead (Pb) and its effects on human: A review  Lead in Food and Foodwares - FDA  Low Level Lead Exposure: History and Discovery  Lead Toxicity: an Australian Perspective  Some US protein powders contain high levels of lead. Can I tell if mine is safe? - the Conversation If you enjoyed this episode, check these out! How much protein do you REALLY need? Norman tried an ice bath so you don't have to Why do hangovers get worse as we age?

Once you go looking, you realise there are scents in everything – from skincare to cleaning supplies to candles. And of course, perfume. Are there any implications to our health from taking in natural and synthetic fragrances from all these products? Norman and Tegan sniff out the evidence when it comes to scent, and whether we should be worried. References: The first chemist in history may have been a female perfumer – here’s how the science of scents has changed since - the Conversation  A Smelling Trip into the Past: The Influence of Synthetic Materials on the History of Perfumery Health and societal effects from exposure to fragranced consumer products – University of Melbourne Effects by inhalation of abundant fragrances in indoor air – An overview  Cleaning at Home and at Work in Relation to Lung Function Decline and Airway Obstruction Cleaning at Home and at Work in Relation to Lung Function Decline and Airway Obstruction Synthetic Endocrine Disruptors in Fragranced Products  Do fragrant products like perfume, toilet paper and baby wipes cause cancer? - Cancer Council  Characterization of phthalates exposure and risk for cosmetics and perfume sales clerks  Chemical exposure and lung function in fragrance industry employees  Butter and Plant-Based Oils Intake and Mortality - JAMA If you enjoyed this episode, check these out! Don't sweat it? Conventional vs natural deodorants Why is everyone suddenly talking about seed oils? Are mobile phones giving us cancer?

Whether you can or not, it feels like a sign of fitness to be able to reach down and touch your toes. But how important is flexibility when it comes to your physical fitness? Is it a necessary part of healthy ageing? Norman and Tegan stretch through the evidence on flexibility – when does it count, and how can you achieve it? References: Genetics of Muscle Stiffness, Muscle Elasticity and Explosive Strength Genetic associations of body composition, flexibility and injury risk with ACE, ACTN3 and COL5A1 polymorphisms in Korean ballerinas Whole-spine dynamic magnetic resonance study of contortionists: anatomy and pathology Practical recommendations on stretching exercise: A Delphi consensus statement of international research experts The ideal stretching routine – Harvard Health How stretching actually changes your muscles - Malachy McHugh for Ted-Ed If you enjoyed this episode, check these out! Working out? Why 'No Pain No Gain' is bull What on earth is grounding?! Can you zap yourself buff with electrical muscle stimulation? You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

The battle between butter and margarine has been happening since margarine was invented in the 19th century. So have we figured out which one is better for your health – butter with its high saturated fat content, or margarine which is an ultra-processed food? Norman and Tegan unpack the winding history of this debate from its inception to the present day. References: The Butter Wars: When Margarine Was Pink – National Geographic  The Butter-Margarine Controversy - 1946 What the margarine vs butter argument says about nutrition – University of Melbourne Dietary fats - Healthdirect  What’s better, butter or margarine? - Diabetes Australia  Serum cholesterol response to replacing butter with a new trans-free margarine in hypercholesterolemic subjects Individual Cholesterol Variation in Response to a Margarine- or Butter-Based Diet: A Study in Families Effects of margarines and butter consumption on lipid profiles, inflammation markers and lipid transfer to HDL particles in free-living subjects with the metabolic syndrome BMI modifies the effect of dietary fat on atherogenic lipids: a randomized clinical trial From margarine to butter: predictors of changing bread spread in an 11-year population follow-up Association between dairy intake and multiple health outcomes: a scoping review of systematic reviews and meta-analyses | European Journal of Clinical Nutrition  Umbrella Review of Systematic Reviews and Meta-analyses on Consumption of Different Food Groups and Risk of All-cause Mortality - ScienceDirect If you enjoyed this episode, check these out! Is emu oil the new snake oil? Is daylight saving time bad for us? Should you be avoiding nightshades? You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

Do you ever wonder while you’re shampooing and conditioning – is this really necessary? The no-poo movement encourages people to ditch their products and turn to homemade concoctions, or nothing at all. Norman and Tegan rinse out the evidence for and against hair care, and how we got here in the first place. References: Clean: A History of Personal Hygiene and Purity Shampoo and Conditioners: What a Dermatologist Should Know? The "No-poo" Craze: What do Gwyneth Paltrow, Kim Kardashian, Adele and Howie Mandel have in common? They don’t "poo" - McGill University Essentials of Hair Care often Neglected: Hair Cleansing Unlocking the secrets of the hair microbiome: From scalp health to therapeutic advances Parabens in Cosmetics - US Food and Drug Administration If you enjoyed this episode, check these out! Can you get away with skipping your daily shower? Which hair loss treatments actually work? Does magnesium work against muscle cramps? You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

It’s marathon season, but whether you’re running 40 kilometres or four you might’ve wondered what it’s doing to your joints. It used to be thought things like osteoarthritis of the knee or the hip were caused by wear and tear, and running made things worse. Norman and Tegan jog through how the evidence has evolved, and answer the question: should you be hopping on the run club trend? References:  Running and your knees - ABC listen Effects of Running on the Development of Knee Osteoarthritis: An Updated Systematic Review at Short-Term Follow-up The Association of Recreational and Competitive Running With Hip and Knee Osteoarthritis: A Systematic Review and Meta-analysis The risk of osteoarthritis with running and aging: a 5-year longitudinal study. - Abstract Can marathon running improve knee damage of middle-aged adults? A prospective cohort study How much running is too much? Identifying high-risk running sessions in a 5200-person cohort study Using metformin to treat knee osteoarthritis - ABC listen Changing the brain to reduce pain and walk the Camino - ABC listen Metabolic syndrome meets osteoarthritis | Nature Reviews Rheumatology Mechanical loading and orthobiologic therapies in the treatment of post-traumatic osteoarthritis (PTOA): a comprehensive review Leisure-Time Running Reduces All-Cause and Cardiovascular Mortality Risk If you enjoyed this episode, check these out! Is sitting the new smoking? Sweaty sauna bathing for better health Is being an Olympian bad for your health? You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

A post from Queensland Health has been ridiculed after for urging people not to kiss their pets or let them sleep in the same bed. So how do the risks of pet ownership stack up to the presumed benefits of having a furry (feathery or scaly) friend? Norman and Tegan take a look at the evidence – and some of its flaws – and reignite the age-old cat vs dog debate. References: If you have a pet as a kid, does this lower your risk of asthma and eczema? | WEHI Zoonotic diseases and pets | American Veterinary Medical Association  Behavioral changes induced by Toxoplasma infection of rodents are highly specific to aversion of cat odors | PNAS Pet Ownership and Quality of Life: A Systematic Review of the Literature Is Dog Ownership Associated with Mental Health? A Population Study of 68,362 Adults Living in England No beneficial associations between living with a pet and mental health outcomes during the COVID-19 pandemic in a large UK longitudinal sample - ScienceDirect Pet ownership, loneliness, and social isolation: a systematic review | Social Psychiatry and Psychiatric Epidemiology The Relationship Between Attachment to Pets and Mental Health and Wellbeing: A Systematic Review  Pet ownership and maintenance of cognitive function in community-residing older adults: evidence from the Baltimore Longitudinal Study of Aging (BLSA) | Scientific Reports Dog owners are more likely to meet physical activity guidelines than people without a dog: An investigation of the association between dog ownership and physical activity levels in a UK community | Scientific Reports  A modest protective association between pet ownership and cardiovascular diseases: A systematic review and meta-analysis | PLOS One Dog, cat, bird, fish, and other pet ownership and mortality: Evidence from the HILDA cohort Long-term stress levels are synchronized in dogs and their owners | Scientific Reports If you enjoyed this episode, check these out! How worried should you be about microplastics? Is daylight saving time bad for us? MSG's messy myths and racist tropes You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

It’s hay fever season, and as you sniffle away next to an air purifier, you might be wondering why we haven’t cured such a common allergy. Allergic rhinitis, as it’s scientifically known, has plagued people for generations. It's thought up to 24 per cent of Australians suffer from it. Norman and Tegan run through what hay fever is, how we identified it and what can be done to treat it.  This episode first aired on October 23, 2024.  References: Allergic Rhinitis: A Review O Rose thou art sick… history of allergic rhinitis I’m considering allergen immunotherapy for my hay fever. What do I need to know? Ingestion of honey improves the symptoms of allergic rhinitis: evidence from a randomized placebo-controlled trial The Potential use of Honey as a Remedy for Allergic Diseases: A Mini Review Can you adapt to allergies or does the dog have to go? You can listen to more episodes of the What’s That Rash? podcast with presenters Norman Swan and Tegan Taylor on the ABC Listen app (Australia) or wherever you get your podcasts. We answer your questions on everything from TikTok wellness trends to wonder drugs and diet myths.

It’s a tale as old as air travel … you’re off on a whirlwind holiday but spend the first week suffering from fatigue. If you ask anyone about jet lag they’ll have their own tips, but what are some evidence-based ways to reset your body clock? Norman and Tegan talk through some of the ways you can adjust to a totally different timezone. References: Time-zone effects on the long-distance air traveler - 1969 Jet lag syndrome: circadian organization, pathophysiology, and management strategies An Abrupt Shift in the Day/Night Cycle Causes Desynchrony in the Mammalian Circadian Center The genetics of mammalian circadian order and disorder: implications for physiology and disease How To Travel the World Without Jet Lag Eastward Jet Lag is Associated with Impaired Performance and Game Outcome in the National Basketball Association Managing Travel Fatigue and Jet Lag in Athletes: A Review and Consensus Statement Melatonin for the prevention and treatment of jet lag | Cochrane Review If you enjoyed this episode, check these out! Chronotypes: Early birds vs night owls Is daylight saving time bad for us? What is the perfect nap duration?

If you haven’t heard of the Don’t Die movement or Bryan Johnson’s Blueprint Protocol, then buckle in. Johnson is a millionaire who is pouring his money into a massive effort to stay as young as possible, for as long as possible. Norman and Tegan unpack the basics of his routine, and some of his whackier attempts to turn back the biological clock. References: DunedinPACE, a DNA methylation biomarker of the pace of aging How old are you really? Are the latest ‘biological age’ tests all they’re cracked up to be? Plasma-Based Strategies for Therapeutic Modulation of Brain Aging Infusion of young donor plasma components in older patients modifies the immune and inflammatory response to surgical tissue injury: a randomized clinical trial | Journal of Translational Medicine Old plasma dilution reduces human biological age: a clinical study Metformin as Anti-Aging Therapy: Is It for Everyone? Targeting ageing with rapamycin and its derivatives in humans: a systematic review - The Lancet Healthy Longevity A Phase 1/2a Follistatin Gene Therapy Trial for Becker Muscular Dystrophy Follistatin Gene Therapy Improves Ambulation in Becker Muscular Dystrophy If you enjoyed this episode, check these out! Is it safe to dose yourself with pre-workout? Can collagen supplements keep your skin supple? Can you train yourself to sleep less?

You go to make a sandwich and notice mould on the corner of a single slice of bread — we've all been there.  So what do you do? Chop off the affected corner? Ditch the single slice and choose bread from further down in the bag? Or chuck the entire bag? Norman and Tegan take on this controversial topic at the World Science Festival in Brisbane.  References: Mycotoxin contamination in moldy slices of bread is mostly limited to the immediate vicinity of the visible infestation Aflatoxins - National Cancer Institute Ergot poisoning: Symptoms, treatment, and history The expert verdict on whether it's ever OK to cut off the mould on food and eat the rest - ABC News Disgust as an adaptive system for disease avoidance behaviour Yucky! How Do Toddlers Learn About Disgust? If you enjoyed this episode, check these out! Why the carnivore diet is so risky Cracking your knuckles: good, bad or just annoying?