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Some people are trading traditional birth control for methods like fertility tracking to avoid getting pregnant.  How effective are these approaches? And why are people attracted to these "natural" methods? Naomi* and Tegan discuss some of these methods, and how side effects of contraceptives might be contributing to this shift. *Dr Naomi Koh Belic is filling in for Norman Swan as he recovers from his knee replacement! Keep an eye out for Dr Naomi's Fact or Fiction on the ABC Science YouTube. References: “Do You Know What Birth Control Actually Does to Your Body?”: Assessing Contraceptive Information on TikTok Hormonal Birth Control Misinformation on TikTok: A Content Analysis of Influencer Narratives Self-reported contraceptive method use at conception among patients presenting for abortion in England: a cross-sectional analysis comparing 2018 and 2023 Reasons for rejecting hormonal contraception in Western countries: A systematic review Contraceptive-Induced Weight Gain—Myth and Reality Review Association of Hormonal Contraception With DepressionPilot Data on the Feasibility And Clinical Outcomes of a Nomegestrol Acetate Oral Contraceptive Pill in Women With Premenstrual Dysphoric DisorderCommon myths and misconceptions surrounding hormonal contraceptionEndometrial cancer and oral contraceptives : an individual participant meta-analysis of 27,276 women with endometrial cancer from 36 epidemiological studiesIf you enjoyed this episode, check these out! How to drive down your cancer riskAt-home DNA tests — what can they tell you?Deep dive on progressive exercise

The world is full of distractions, and our biggest one might be the phone in our hands. Many people feel their attention spans have suffered from endlessly "doomscrolling" online. Norman and Tegan discuss what has actually happened to our attention in the age of social media. Check out Science Friction: Brain Rot for more on what technology is doing to our brains. References: A comprehensive review of attention tests: can we assess what we exactly do not understand?Quantifying attention span across the lifespanAre attention spans really shrinking? What the science saysIs there a Flynn effect for attention? Cross-temporal meta-analytical evidence for better test performance (1990–2021)Memory failure predicted by attention lapsing and media multitaskingCognitive control in media multitaskersDigital self-control interventions for distracting media multitasking - A systematic review“Phone in the Room, Mind on the Roam”: Investigating the Impact of Mobile Phone Presence on DistractionBrain Drain: The Mere Presence of One’s Own Smartphone Reduces Available Cognitive Capacity If you enjoyed this episode, check these out! Could headphones be damaging our ears?Headaches: causes, cures and exercise?!There's a lot of fog around brain fog

We've received questions from listeners worried that other people can smell their age. So is "old person smell" a thing? And do you need expensive soap to combat it? Norman and Tegan discuss some of the science underpinning this supposed phenomenon, and where marketing tricks play a part. References: 2-Nonenal Newly Found in Human Body Odor Tends to Increase with AgingMeasurement of 2-nonenal and diacetyl emanating from human skin surface employing passive flux sampler—GCMS systemAnalyses of volatile organic compounds from human skin The effect of polyphenol-containing soap on reducing body odor in middle-aged and elderly menThe Smell of Age: Perception and Discrimination of Body Odors of Different Ages Diet quality and the attractiveness of male body odorIf you enjoyed this episode, check these out! Don't sweat it? Conventional vs natural deodorantsWhat has your nose got to do with sleep?

Introvert or extrovert, we've all been told about the importance of social connection to our health. Isolation can have knock-on effects for your brain health – and the health of the rest of your body. Norman and Tegan unpack how many friends the average person "needs" and what happens when you're alone but not lonely. References: Social ties and health: the benefits of social integrationSocial isolation: a predictor of mortality comparable to traditional clinical risk factorsThe Connection Prescription: Using the Power of Social Interactions and the Deep Desire for Connectedness to Empower Health and Wellness Friendships, Subjective Age, and Life Satisfaction of Women in Midlife The American Friendship Project: A report on the status and health of friendship in AmericaSocial connection linked to improved health and reduced risk of early death – World Health Organization Differential Social Cognitive Performance in Older Adults With Mild Cognitive Impairment and DementiaIntrovert vs Social Anxiety: How to tell the difference If you enjoyed this episode, check these out! Is retirement bad for you?Chronotypes: early birds vs night owlsShould you aim for an alkaline lifestyle?

You might've heard you'll burn more fat if you exercise in the morning before, or in lieu of breakfast. There is some research to back that claim up, but the science on fasted exercise isn’t clear cut. Norman and Tegan work through the evidence on exercising on an empty stomach, and what you can do to maximise your workouts. References: Effects of fasted vs fed-state exercise on performance and post-exercise metabolism: A systematic review and meta-analysisEffect of Overnight Fasted Exercise on Weight Loss and Body Composition: A Systematic Review and Meta-AnalysisInterval training in the fed or fasted state improves body composition and muscle oxidative capacity in overweight womenEffects of exercise before or after meal ingestion on fat balance and postprandial metabolism in overweight menEffects of time-restricted eating with exercise on body composition in adults: a systematic review and meta-analysisExercising in the Fasted State Reduced 24-Hour Energy Intake in Active Male Adults Appetite, energy intake and resting metabolic responses to 60 min treadmill running performed in a fasted versus a postprandial state Fasting Before Evening Exercise Reduces Net Energy Intake and Increases Fat Oxidation, but Impairs Performance in Healthy Males and FemalesFasted cardio is an attempt to burn stored fatIf you enjoyed this episode, check these out! What's the best time of day to exercise?What are the health benefits of coffee?Do glasses make your eyesight worse?

Sit back and relax. Close your eyes. Imagine you're sitting on a calm beach. Now, do you feel more open to suggestion? Hypnotherapy has been around for centuries, and you might've heard about it being used for everything from PTSD to addiction and even IBS. Norman and Tegan guide us through the evidence for using hypnosis in a therapeutic setting, and whether there are any downsides. References: Brain Activity and Functional Connectivity Associated with HypnosisNot everyone can be hypnotized - and researchers are one step closer to understanding why Functional Brain Basis of HypnotizabilityA Systematic Review of Hypnosis for Clinical Pain ReliefThe effectiveness of hypnosis for pain relief: A systematic review and meta-analysis of 85 controlled experimental trialsHypnosis as a non-pharmacological intervention for invasive medical procedures - A systematic review and meta-analytic updateGut-directed hypnotherapy for IBS: what is it and what are the options?Gut-Directed Hypnotherapy for Irritable Bowel Syndrome: A Systematic Review and Meta-AnalysisDoes hypnotherapy help people who are trying to stop smoking? - Cochrane ReviewEffectiveness of hypnosis in adults with posttraumatic stress disorder (PTSD)A Meta-Analysis of Hypnotherapeutic Techniques in the Treatment of PTSD SymptomsHypnotherapy in the Treatment of Chronic Combat-Related PTSD Patients Suffering From Insomnia: A Randomized, Zolpidem-Controlled Clinical TrialEricksonian hypnotherapy versus cognitive behavioral therapy for post-traumatic stress disorderThe Prefrontal Cortex and Suggestion: Hypnosis vs. Placebo EffectsIf you enjoyed this episode, check these out! What's the deal with night terrors?Can tapping calm your nervous system?Why do we dream?

As we age, levels of a vital molecule called nicotinamide adenine dinucleotide (NAD+) decline. Could reversing this be the key to eternal youth? There’s huge interest in NAD-boosting supplements like nicotinamide mononucleotide (NMN). But is there good evidence that they can help us live longer, healthier? Norman and Tegan unpack how NAD+ became the focus of anti-aging proponents. This episode first aired on November 4, 2024. References: NAD+ metabolism and its roles in cellular processes during ageingNAD+ in Brain Aging and Neurodegenerative DisordersWhat is really known about the effects of nicotinamide riboside supplementation in humansDietary Supplementation With NAD+-Boosting Compounds in Humans: Current Knowledge and Future DirectionsThe use of a systems approach to increase NAD+ in human participantsSpecific ablation of Nampt in adult neural stem cells recapitulates their functional defects during aging

Shift workers make a lot of sacrifices to keep the world running. What are they sacrificing in terms of their own health? There are harms associated with working at all hours against your body clock. Norman and Tegan work through what those are, and what you can do to protect against them. References: 5 long-term health effects of shift work Shift work can harm sleep and health: What helps?Coping with shift work Shift work and health outcomes: an umbrella review of systematic reviews and meta-analyses of epidemiological studiesShift work and long work hours and their association with chronic health conditions: A systematic review of systematic reviews with meta-analysesRelationship between long-term shift work; night work; sleep deficiency and stroke: A systematic review and meta-analysis Shifting Rhythms: A Systematic Review Exploring the Multifaceted Effects of Shift Work and Circadian Disruption on Employee Cardiovascular HealthExercise interventions for sleep and cognitive dysfunction in shift workers: a systematic review of randomized trials If you enjoyed this episode, check these out! What is the perfect nap duration?Chronotypes: early birds vs night owlsWhy do some people pee more often?

When you're done with your weekly grocery shop, how colourful is your trolley? We know eating lots of fruits and vegetables is good for you, but colour could matter. Norman and Tegan discuss what gives fruit and veggies their hue and whether it's important when it comes to healthy eating. References: Phytonutrients: Paint your plate with the colours of the rainbowClinical Evidence of the Benefits of Phytonutrients in Human HealthcareEat a Rainbow – Nutrition AustraliaPhytochemicals: Principles and PracticeWhat’s the Difference Between Sweet Potatoes and Potatoes?Role of Phytonutrients in the Prevention and Treatment of Chronic Diseases: A Concrete ReviewMajor phytochemicals, their sources, active sites, and the related health benefitsEffect of Fruit and Vegetable Consumption on Human Health: An Update of the LiteratureAdding variety to your diet lowers disease risk. But what does variety mean?Which Colour of Bell Pepper Has Most Nutrients? If you enjoyed this episode, check these out! Should you be eating more fruit?Why Norman won't shut up about the Mediterranean dietWhat are the health benefits of coffee?

How much time does your oral hygiene routine take? You brush, floss, interdent, maybe even use a tongue scraper. Is using a mouthwash going to give you any additional benefit? Or could you be doing some harm? Norman and Tegan answer questions about the effectiveness of mouthwash, what it does to your oral microbiome and why there might be a link to blood pressure. References: Oral microbiome: Unveiling the fundamentals Effectiveness of Mouthwashes in Managing Oral Diseases and Conditions: Do They Have a Role?Effect of Adjunctive Use of Commercial Daily Mouthwashes on Periodontal Health: An Umbrella Review Effect of post-brushing mouthrinse solutions on salivary fluoride retentionMouthwash Effects on the Oral Microbiome: Are They Good, Bad, or Balanced?Effects of chlorhexidine and a polyherbal mouthwash on the oral microbiome and user satisfaction: a randomized controlled trial The Effects of Antimicrobial Mouthwashes on Systemic Disease: What Is the Evidence? Oral hygiene, mouthwash usage and cardiovascular mortality during 18.8 years of follow-upDoes Mouthwash Use Affect Oral Cancer Risk? A Comprehensive Systematic Review and Meta-Analysis An update on mouthwashes: advice for dental practitioners If you enjoyed this episode, check these out! Can flossing benefit more than your teeth?How risky is sharing a toothbrush?Should you opt for aluminium-free deodorant?

Continuous glucose monitors, or CGMs, have transformed how people with diabetes manage their blood sugar. But in wellness circles, more and more people without diabetes are being encouraged to try these devices. Norman and Tegan get to the bottom of what these devices can actually tell you, and the potential harms. References: The wellness inspired rise of continuous glucose monitors for people without diabetes, including those with metabolic disorders – BMJ featuresContinuous glucose monitoring in non-diabetic populations: a systematic review of observational and interventional studies with meta-analysis  Blood glucose monitoring devices: current consideration – Australian Prescriber The Use of Continuous Glucose Monitoring to Diagnose Stage 2 Type 1 DiabetesAssociations of continuous glucose monitor derived time in range and glycaemic variability with diet lifestyle and demographicsDifferent Glucose Variability in Women With Polycystic Ovary Syndrome With and Without Insulin Resistance: A Pilot StudyUnderstanding the benefits and psychological burdens of using continuous glucose monitoring for lifestyle change: A mixed-methods cross-sectional study Unintended Consequences: The Intersection of Diabetes Technology and Disordered Eating Risk If you enjoyed this episode, check these out! Should we all be taking fish oil?Tonsils, appendix, gallbladder: is anything actually useless?Should you wait to swim after eating?

Not many people would argue that rest isn’t important, but how would you define a rest day? For an elite athlete a rest day could be going for a long walk. For your average person it could mean sitting on the couch. Norman and Tegan ask – why is rest important, and do you need it to make progress in the gym? References: 'No pain, no gain' debunked: Why post-exercise soreness is not essential for building muscleSkeletal muscle and resistance exercise training; the role of protein synthesis in recovery and remodelingEffects of Different Between Test Rest Intervals in Reproducibility of the 10-Repetition Maximum Load Test: A Pilot Study with Recreationally Resistance Trained MenThe time course for elevated muscle protein synthesis following heavy resistance exercise Recovery and Performance in Sport: Consensus Statement Effects of Consecutive Versus Non-consecutive Days of Resistance Training on Strength, Body Composition, and Red Blood Cells Nonconsecutive versus consecutive-day resistance training in recreationally trained subjects Fatigue, pain, and the recovery of neuromuscular function after consecutive days of full-body resistance exercise in trained men Effects of Consecutive Days of Exercise and Recovery on Muscle Mechanical Function How much is too much? (Part 1) International Olympic Committee consensus statement on load in sport and risk of injury  If you enjoyed this episode, check these out! Is retirement bad for you?Do the benefits of creatine go beyond the gym?Diet vs exercise: which is more important?

Have you ever spritzed your pillow with lavender and wondered, is this actually doing anything? There are some surprising ways that smells can affect sleep, and it might have something to do with how our brains work. Norman and Tegan discuss how smells, good and bad, could affect your nightly snooze. References: From antiquity to modern hygiene: the archaeological and medicinal legacy of lavender as a promising antimicrobial agentLavender and sleep: A systematic review of the evidence How Smell Affects Your Sleep – Sleep Foundation Reciprocal relationships between sleep and smell Subjectively intense odor does not affect dream emotions during rapid eye movement sleep Nocturnal exposure to a preferred ambient scent does not affect dream emotionality or post-sleep core affect valence in young adults Olfactory Aversive Conditioning during Sleep Reduces Cigarette-Smoking BehaviorIf you enjoyed this episode, check these out! Is farting a sign your gut microbiome is happy?Is melatonin the answer to a good night's sleep?Is a vibration plate worth the cost?

Do you feel better after a good cry, or do you feel worse than ever? There can be a lot to cry about, good or bad: a break-up, a milestone, a tragedy, a sappy movie. Norman and Tegan discuss why we evolved to cry, and the purpose it serves as we get older. References: The Riddle of Human Emotional Crying: A Challenge for Emotion ResearchersThe neurobiology of human cryingEmotional expression in human and non-human great apesUltra-processed food intake, cognitive function, and dementia risk: A cross-sectional study of middle-aged and older Australian adultsIf you enjoyed this episode, check these out! Butter vs margarine: what's better for you?How much protein do you REALLY need?Why is yawning contagious?

You might be hearing a lot about ultra-processed foods, or UPFs, and how we should all be avoiding them. But you might be struggling with figuring out what exactly IS an ultra-processed food. Sweetened drinks, sure. What about bread? Yoghurt? Norman and Tegan unpack why it isn’t a simple question, and where the evidence stands on the health consequences. *A previous version of this episode may have implied that the Food Standards Australia New Zealand (FSANZ) board is comprised of current food industry representatives that are directly involved in setting food policy. This was edited on 12/08/2026.  References: Ultra-Processed Foods and Human Health - The Lancet seriesDiet quality and processed foods – Food Standards Australia and New ZealandMost of the Foods We Eat Are Ultra-Processed. Are They All Unhealthy? - Johns Hopkins Bloomberg School of Public HealthTrends of obesity and underweight in older children and adolescents in the United States, Brazil, China, and RussiaUltra-processed products are becoming dominant in the global food systemThe UN Decade of Nutrition, the NOVA food classification and the trouble with ultra-processingUltra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analysesUltra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food IntakeThe collapse of the food matrix: how ultra-processed foods impact satiety and metabolism by altering physical structure beyond nutrient composition If you enjoyed this episode, check these out! Is gluten really the enemy?Why is everyone suddenly talking about seed oils?Why Norman won't shut up about the Mediterranean diet