What's That Rash?

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 lifespan
• Are attention spans really shrinking? What the science says
• Is 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 multitasking
• Cognitive control in media multitaskers
• Digital 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 Distraction
• Brain Drain: The Mere Presence of One’s Own Smartphone Reduces Available Cognitive Capacity

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• 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 Aging
• Measurement of 2-nonenal and diacetyl emanating from human skin surface employing passive flux sampler—GCMS system
• Analyses of volatile organic compounds from human skin
• The effect of polyphenol-containing soap on reducing body odor in middle-aged and elderly men
• The Smell of Age: Perception and Discrimination of Body Odors of Different Ages
• Diet quality and the attractiveness of male body odor

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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 integration
• Social isolation: a predictor of mortality comparable to traditional clinical risk factors
• The 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 America
• Social 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 Dementia
• Introvert vs Social Anxiety: How to tell the difference

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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-analysis
• Effect of Overnight Fasted Exercise on Weight Loss and Body Composition: A Systematic Review and Meta-Analysis
• Interval training in the fed or fasted state improves body composition and muscle oxidative capacity in overweight women
• Effects of exercise before or after meal ingestion on fat balance and postprandial metabolism in overweight men
• Effects of time-restricted eating with exercise on body composition in adults: a systematic review and meta-analysis
• Exercising 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 Females
• Fasted cardio is an attempt to burn stored fat

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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 Hypnosis
• Not everyone can be hypnotized - and researchers are one step closer to understanding why
• Functional Brain Basis of Hypnotizability
• A Systematic Review of Hypnosis for Clinical Pain Relief
• The effectiveness of hypnosis for pain relief: A systematic review and meta-analysis of 85 controlled experimental trials
• Hypnosis as a non-pharmacological intervention for invasive medical procedures - A systematic review and meta-analytic update
• Gut-directed hypnotherapy for IBS: what is it and what are the options?
• Gut-Directed Hypnotherapy for Irritable Bowel Syndrome: A Systematic Review and Meta-Analysis
• Does hypnotherapy help people who are trying to stop smoking? - Cochrane Review
• Effectiveness of hypnosis in adults with posttraumatic stress disorder (PTSD)
• A Meta-Analysis of Hypnotherapeutic Techniques in the Treatment of PTSD Symptoms
• Hypnotherapy in the Treatment of Chronic Combat-Related PTSD Patients Suffering From Insomnia: A Randomized, Zolpidem-Controlled Clinical Trial
• Ericksonian hypnotherapy versus cognitive behavioral therapy for post-traumatic stress disorder
• The Prefrontal Cortex and Suggestion: Hypnosis vs. Placebo Effects

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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 ageing
• NAD+ in Brain Aging and Neurodegenerative Disorders
• What is really known about the effects of nicotinamide riboside supplementation in humans
• Dietary Supplementation With NAD+-Boosting Compounds in Humans: Current Knowledge and Future Directions
• The use of a systems approach to increase NAD+ in human participants
• Specific 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 studies
• Shift work and long work hours and their association with chronic health conditions: A systematic review of systematic reviews with meta-analyses
• Relationship 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 Health
• Exercise interventions for sleep and cognitive dysfunction in shift workers: a systematic review of randomized trials

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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 rainbow
• Clinical Evidence of the Benefits of Phytonutrients in Human Healthcare
• Eat a Rainbow – Nutrition Australia
• Phytochemicals: Principles and Practice
• What’s the Difference Between Sweet Potatoes and Potatoes?
• Role of Phytonutrients in the Prevention and Treatment of Chronic Diseases: A Concrete Review
• Major phytochemicals, their sources, active sites, and the related health benefits
• Effect of Fruit and Vegetable Consumption on Human Health: An Update of the Literature
• Adding variety to your diet lowers disease risk. But what does variety mean?
• Which Colour of Bell Pepper Has Most Nutrients?

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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 retention
• Mouthwash 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-up
• Does Mouthwash Use Affect Oral Cancer Risk? A Comprehensive Systematic Review and Meta-Analysis
• An update on mouthwashes: advice for dental practitioners

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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 features
• Continuous 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 Diabetes
• Associations of continuous glucose monitor derived time in range and glycaemic variability with diet lifestyle and demographics
• Different Glucose Variability in Women With Polycystic Ovary Syndrome With and Without Insulin Resistance: A Pilot Study
• Understanding 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

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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 muscle
• Skeletal muscle and resistance exercise training; the role of protein synthesis in recovery and remodeling
• Effects of Different Between Test Rest Intervals in Reproducibility of the 10-Repetition Maximum Load Test: A Pilot Study with Recreationally Resistance Trained Men
• The 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
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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 agent
• Lavender 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 Behavior

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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 Researchers
• The neurobiology of human crying
• Emotional expression in human and non-human great apes
• Ultra-processed food intake, cognitive function, and dementia risk: A cross-sectional study of middle-aged and older Australian adults

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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 series
• Diet quality and processed foods – Food Standards Australia and New Zealand
• Most of the Foods We Eat Are Ultra-Processed. Are They All Unhealthy? - Johns Hopkins Bloomberg School of Public Health
• Trends of obesity and underweight in older children and adolescents in the United States, Brazil, China, and Russia
• Ultra-processed products are becoming dominant in the global food system
• The UN Decade of Nutrition, the NOVA food classification and the trouble with ultra-processing
• Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses
• Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake
• The collapse of the food matrix: how ultra-processed foods impact satiety and metabolism by altering physical structure beyond nutrient composition

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• Why Norman won't shut up about the Mediterranean diet

The modification and removal of body hair has been going on for centuries, but our reasons for it have evolved.

Some believe it’s more hygienic to remove, others argue it’s against our nature to be so hairless.

Norman and Tegan trim the evidence on body hair: leg, armpit, pubic and even inside your nose.

References:

• Trends in body hair removal as depicted through art
• Getting plucked: the history of hair removal - ABC
• Effects of pubic hair grooming on women’s sexual health: a systematic review and meta-analysis
• Bare necessity? Public health implications of removing pubic hair
• Effect of Physical and Chemical Hair Removal Methods on Skin Barrier Function in vitro: Consequences for a Hydrophilic Model Permeant
• Using the Hair Removal Laser in the Axillary Region and its Effect on Normal Microbial Flora
• Shaving of axillary hair has only a transient effect on perceived body odor pleasantness
• Cadaver research leads to prestigious science award - the Science Show
• Does nasal hair (vibrissae) density affect the risk of developing asthma in patients with seasonal rhinitis?
• 6 ways to remove unwanted hair - American Association of Dermatology

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Ashwagandha supplements are rising in popularity, but the herb has been used for hundreds of years in Ayurvedic medicine.

The supposed benefits are broad – from stress to sleep, athletic performance and boosting testosterone.

Norman and Tegan explore where the evidence stands, and uncertainties about potential risks.

References:

• An Overview on Ashwagandha: A Rasayana (Rejuvenator) of Ayurveda
• Chemical composition, cytotoxic and pro-inflammatory enzyme inhibitory properties of Withania somnifera (L.) Dunal root extracts
• Chemical Composition, Biological Activity, and Health-Promoting Effects of Withania somnifera for Pharma-Food Industry Applications
• Clinical and Research Information on Drug-Induced Liver Injury
• Ashwagandha: Is it helpful for stress, anxiety, or sleep?
• Exploring the efficacy and safety of a novel standardized ashwagandha (Withania somnifera) root extract in adults experiencing high stress and fatigue in a randomized, double-blind, placebo-controlled trial
• A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha (Withania somnifera) in Aging, Overweight Males

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When you're going through a stressful time it can have knock-on effects on your routine.

Sleep, diet, exercise routines can be thrown out of whack. And when that stress goes for weeks or months, it can have a serious impact.

Norman and Tegan unpack the various forms of chronic stress, like burnout, and how they can disrupt your health.

References:

• Chronic Stress - ScienceDirect
• Physiology, Stress Reaction
• The impact of stress on body function: A review
• Stressor-Specific Microbiota Intervention
• Stress and the gastrointestinal tract
• B cells and the stressed brain: emerging evidence of neuroimmune interactions in the context of psychosocial stress and major depression
• Stress, depression, the immune system, and cancer
• The effect of multiple adverse childhood experiences on health: a systematic review and meta-analysis
• 11 healthy ways to handle life’s stressors - American Psychological Association
• Stress-related conditions such as adjustment disorder and clinical burnout can be effectively treated with a 12-week cognitive behavioural programme, both when delivered as a face-to-face treatment and when delivered via the internet

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Sea sickness, car sickness, space sickness – when it comes down to it, it’s all the same.

But not everybody suffers the same. Some people are even lucky enough to grow out of motion sickness.

Norman and Tegan talk about what’s going on when the world goes topsy-turvy, and what you can do about it.

References:

• Motion Sickness
• Validating sensory conflict theory and mitigating motion sickness in humans with galvanic vestibular stimulation - Nature
• Are evolutionary hypotheses for motion sickness "just-so" stories?
• Three studies of motion sickness susceptibility – Federal Aviation Authority
• Genetic variants associated with motion sickness point to roles for inner ear development, neurological processes and glucose homeostasis
• Motion sickness diagnostic criteria: Consensus Document of the Classification Committee of the Bárány Society
• Survey of motion sickness susceptibility in children and adolescents aged 3 months to 18 years
• Hopkins History Moments: Neil A. Grauer explains how Hopkins expertise helped prevent seasickness
• Remedies for motion sickness: What works? - Harvard Health

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Lately there have been lots of scary headlines about cancer rates rising in younger adults.

What can you do to drive down your cancer risk?

Norman and Tegan offer some practical tips, and discuss what's in your control versus what isn't.

References:

• Overview of cancer in Australia, 2025 - Australian Institute of Health and Welfare
• Effects of diets on risks of cancer and the mediating role of metabolites
• Be physically active – Cancer Council
• Exercise packs a punch in fending off cancer – the Health Report
• “You do not get cancer by chance”: Communicating the role of environmental causes in cancer diseases and the risk of a “guilt rhetoric”

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Our calcium needs can increase as we age, especially for women going through menopause.

Most Australians aren’t getting enough calcium from their diet, so are supplements a good option?

Norman and Tegan discuss the conflicting evidence on calcium – in particular, could it be good for your bones, but bad for your heart?

References:

• Calcium supplements have 'very little place' in modern medicine - the Health Report
• Nutrient Reference Values - Calcium
• Effect of age on calcium absorption in postmenopausal women
• Biochemical Variables in Pre- and Postmenopausal Women: Reconciling the Calcium and Estrogen Hypotheses
• Calcium Content of Common Foods - Healthy Bones Australia
• Choosing a calcium supplement: What you should know about taking calcium to boost your nutrients
• Calcium Supplements and Risk of Cardiovascular Disease: A Meta-Analysis of Clinical Trials
• Association Between Calcium Supplementation and the Risk of Cardiovascular Disease and Stroke: A Systematic Review and Meta-Analysis
• Association Between Calcium Supplementation and Recurrence of Cardiovascular Events in Patients With Cardiovascular Disease: A Population‐Based Cohort Study
• Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10‐Year Follow‐up of the Multi‐Ethnic Study of Atherosclerosis (MESA)
• Oral Calcium Supplements Associate With Serial Coronary Calcification: Insights From Intravascular Ultrasound

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