Your Brain On

Testosterone for women: what the evidence actually shows vs. what social media is selling you.

Testosterone has become the hormone every midlife woman is told she is missing: the third hormone lost at menopause, the fix for brain fog, low energy, stubborn weight, and thinning muscle.

The science tells a different and more reassuring story.

In this episode, Dr. Ayesha Sherzai sits down with Professor Susan Davis, MBBS, FRACP, PhD, the clinician-researcher and academic endocrinologist who gathered much of the data and helped write the global guidelines, to separate what the research supports from what is simply being sold.

Your Brain On... Testosterone [Season 7, Episode 7]

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In this episode:

• Why testosterone does not crash at menopause the way estrogen does, and what actually changes across a woman's life
• What the research shows about testosterone and memory, brain fog, and dementia risk
• The real story on testosterone for muscle, bone, and anti-aging claims
• Why women tend to gain a little weight on testosterone rather than lose it
• The one use with genuine evidence behind it: low sexual desire after menopause that causes real distress
• Why more is not better, and what high-dose testosterone actually does
• What is really inside compounded creams, injections, and testosterone pellets sold at med spas
• Why routine testosterone blood testing generates bills and anxiety rather than answers
• Why there is no such thing as testosterone deficiency in women
• How to tell an evidence-based clinician from a sales pitch
• What genuinely protects a woman's aging brain, and why connection matters more than any hormone

Professor Susan Davis is a consulting endocrinologist at Monash University in Melbourne, where she directs a leading women's health research program. She has studied testosterone in women since the 1990s and is the lead author of the Global Consensus Position Statement on the Use of Testosterone Therapy for Women, endorsed by the International Menopause Society, The Endocrine Society, and menopause and obstetric societies around the world.

References:

Does testosterone crash at menopause? Wang Y, Islam RM, Bond M, Davis SR. Testosterone and pre-androgens by age and menopausal stage at midlife: findings from a cross-sectional study. EBioMedicine. 2025;121:105972. PMID: 41106025. Davis SR, Bell RJ, Robinson PJ, et al. Testosterone and estrone increase from the age of 70 years: findings from the Sex Hormones in Older Women Study. J Clin Endocrinol Metab. 2019;104(12):6291–6300. PMID: 31408149. Islam RM, Bell RJ, Handelsman DJ, Robinson PJ, Wolfe R, Davis SR. Longitudinal changes over three years in sex steroid hormone levels in women aged 70 years and over. Clin Endocrinol (Oxf). 2021;94(3):443–448. PMID: 33351205.

Does testosterone improve memory or protect against dementia? Sultana F, Davis SR, Wolfe RS, McNeil JJ, Islam RM. Associations between blood sex hormones, cognitive decline and incident dementia in community-dwelling older Australian women: a prospective cohort study. Climacteric. 2025;28(4):446–455. PMID: 40085743. Sultana F, Islam RM, Davis SR. Associations between declining testosterone concentrations and cognitive performance in community-dwelling older Australian women: a prospective cohort study. Climacteric. 2026;29(1):46–52.

What does testosterone therapy actually do? Islam RM, Bell RJ, Green S, Page MJ, Davis SR. Safety and efficacy of testosterone for women: a systematic review and meta-analysis of randomised controlled trial data. Lancet Diabetes Endocrinol. 2019;7(10):754–766. PMID: 31353194.

What do the global guidelines say? Davis SR, Baber R, Panay N, et al. Global Consensus Position Statement on the Use of Testosterone Therapy for Women. J Clin Endocrinol Metab. 2019;104(10):4660–4666. PMID: 31498871.

Can a blood test diagnose low testosterone? Wang Y, Islam RM, Hodge A, Handelsman DJ, Karim MN, Bond M, Davis SR. Associations between testosterone and pre-androgens and sexual function: findings from the Australian Women's Midlife Years Study. Fertility and Sterility. 2026.

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Hosted by Drs. Ayesha & Dean Sherzai.

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The neurologist who built the test that was used on the President of the United States explains what memory tests actually tell you, and why even a perfect score isn't the whole picture.

We sit down with Dr. Ziad Nasreddine, the neurologist who created the Montreal Cognitive Assessment (MoCA), to look at how memory is actually measured, why a score can be shaped by your education and how comfortable you are with tests, and what separates a quick screen from a full neuropsychological evaluation.

The conversation opens with a patient who passed a short memory screen but whose family knew something was wrong, and what a deeper test revealed. From there it moves to how the MoCA works, how it became famous after a presidential exam (and the memorization problem that followed), why your education and nerves can shift a score, and why the real progress against dementia is happening in detection and prevention, not treatment.

A memory test is not a verdict. Its value is early, honest information, and what you can do once you have it.

In this episode:

• What the Montreal Cognitive Assessment (MoCA) measures, and why it was designed to catch the earliest changes rather than advanced dementia
• How a quick memory screen differs from a full neuropsychological evaluation, and what a score actually represents
• Why education, language, and familiarity with testing can change your score even when your cognition is fine
• The story behind the MoCA becoming famous after a US presidential exam, and the memorization problem that followed
• XpressO, a free at-home cognitive pre-screener, and what a green result does and does not mean
• Why detection and prevention, not treatment, are where the real progress against dementia is happening right now
• The difference between slowing decline and reversing it, and why a diagnosis of dementia cannot be undone
• What the 2024 Lancet Commission's modifiable risk factors mean for your everyday choices
• How movement and social connection show up in the data on cognitive decline
• How to read a health headline: effect size, clinical versus statistical significance, and why a small change can be sold as a breakthrough

Dr. Ziad Nasreddine is a neurologist and the creator of the Montreal Cognitive Assessment (MoCA), which he first developed in 1996 and spent nine years validating. It has since been translated into more than 50 languages and is used in over 100 countries, making it one of the most widely used cognitive tests in medicine. He completed his cognitive neurology fellowship at UCLA under Dr. Jeffrey Cummings. His more recent work includes XpressO, a free at-home pre-screener, and MoCA Solo, an AI-administered version of the test.

Resources:

• The MoCA (Montreal Cognitive Assessment)
• XpressO (free at-home cognitive pre-screener)
• Our 2026 Brain Health Retreat

Hosted by Drs. Ayesha & Dean Sherzai

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We're more connected than ever, yet, we've never been lonelier.

We sit down with neuroscientist Dr. Ben Rein, author of Why Brains Need Friends, to look at what isolation does to the brain and body, why we badly underestimate our own social skills, and how to build real connection back into ordinary life.

The conversation opens 45,000 years ago, with a healed bone that points to one of the earliest signs of human caregiving. From there it moves to the present: why "rejection hurts because it used to kill," how chronic loneliness raises cortisol and inflammation, and why regular social connection lowers the risk of dementia, heart disease, diabetes, anxiety, and depression.

In this episode:

• The 45,000-year-old skeleton (Shanidar 1) that points to the origins of human caregiving and friendship
• Why "rejection hurts because it used to kill," and how that ancient circuitry still runs in the modern brain
• What chronic loneliness does to cortisol, inflammation, and long-term disease risk
• The research on solitary confinement and why isolation tracks with higher mortality
• How regular social connection lowers the risk of dementia, heart disease, diabetes, anxiety, and depression
• The commuter-train experiment that shows strangers want to connect far more than we expect
• Introverts vs extroverts: the "plant watering" model for finding your own social dose
• The social diet: why a healthy social life, like a healthy plate, needs variety
• Why digital interaction flattens the social cues your brain evolved to read
• The Dunbar number, the loss of "third places," and the young men's loneliness epidemic
• One small, science-backed thing to try this week

Dr. Ben Rein is a neuroscientist, science communicator, and author of Why Brains Need Friends: The Neuroscience of Social Connection (Penguin Random House). He is chief science officer of the Mind Science Foundation, an adjunct lecturer at Stanford University, and a clinical assistant professor at SUNY Buffalo. His research focuses on the neuroscience of social interaction, and he teaches neuroscience to more than 1 million followers online.

Resources:

• Why Brains Need Friends (book)
• Dr. Ben Rein
• Our 2026 Brain Health Retreat

Hosted by Drs. Ayesha & Dean Sherzai

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Researchers found people who ate these 9 foods consistently had brains that aged 7.5 years slower.

Not a supplement stack, not a protocol, not a hack. A pattern of real food that keeps showing up across decades and across the world.

It's called the MIND diet, and it's what we're breaking down in this episode.

We explore the scoring system behind the MIND diet with a registered dietician who came to brain health through her own mother's Alzheimer's diagnosis, and who has spent 20 years helping real women in real kitchens make these changes stick.

In this episode, you'll learn:

• What the MIND diet actually is: a hybrid of the Mediterranean and DASH diets built at Rush University to target brain health specifically, and why the acronym uses the word "delay," not "reversal"
• The 10 brain-healthy foods and 5 foods to limit, and why the scoring system rewards you for progress, not perfection: full adherence lowered Alzheimer's risk by 53%, and even moderate adherence cut it by 35%
• Why leafy greens are the single most consistent finding in the field and the one change worth making first
• How berries, beans, nuts, olive oil, and omega-3s each contribute to the pattern, and why frozen and canned versions count just as much as fresh
• The problem with the term "ultra-processed food": why yogurt, tofu, and soy milk get mislabeled, and how a dietician actually talks to clients about it
• Why the protein conversation has gotten louder than the evidence: what 1.2 to 1.6 grams per kilogram actually looks like, and why 150 grams a day is not a universal target
• Why wine was quietly dropped from the MIND diet recommendations and what the current evidence says about alcohol and brain health
• Midlife as a metabolic inflection point: why perimenopause and menopause change the equation for cardiovascular and brain health, and why it is not too late to start
• The 2024 Lancet Commission report adding LDL cholesterol as a modifiable risk factor for dementia, and when diet alone is not enough to manage it
• A week-one assignment: one leafy green every day for seven days, then build from there

Barbie Boules is a registered dietician with more than 20 years of experience in women's health and brain health nutrition. Her mother was diagnosed with Alzheimer's in 2022, and her work bridges clinical evidence with practical, accessible meal planning for women in midlife.

Follow Barbie: https://www.instagram.com/the_cognition_dietitian

Hosted by Drs. Ayesha & Dean Sherzai

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It's 3 AM and your brain won't shut off. About 1 in 10 adults meets the clinical definition of chronic insomnia, and most never get treated. Instead, they scroll through an endless aisle of magnesium gummies, melatonin, and $300 trackers that don't address the real problem.

We brought in a neurologist and a psychologist who never spoke to each other and landed on almost the exact same conclusions.

In this episode, you'll learn:

• How the brain's glymphatic cleaning system works during sleep and why chronic insomnia is a brain health problem
• Why melatonin is a darkness signal, not a sleeping pill, and how nocturnal animals prove the point
• A sleep neurologist's honest 1-to-10 ratings of every sleep aid you've heard of: magnesium (2/10), CBT-I (10/10), alcohol (-10/10), and 12 more
• What orthosomnia is and why your sleep tracker might be making your insomnia worse
• Why perimenopause and menopause create what one expert calls "a perfect storm" for sleep disruption, and why doctors keep missing sleep apnea in women
• How CBT-I works: sleep restriction, stimulus control, and why your therapist will tell you to spend less time in bed, not more
• The data showing CBT-I may outperform hormone therapy for menopausal insomnia
• ACT therapy for insomnia: a different approach for people who get more anxious from CBT-I
• Blue light, naps, the 8-hour rule, catching up on weekends: what holds up and what doesn't
• Five steps to start tonight, and why you should pick just two

Dr. Sujay Kansagra is a pediatric neurologist and sleep medicine specialist at Duke University, director of Duke's Pediatric Neurology Sleep Medicine Program, and author of "My Child Won't Sleep." Follow Dr. Kansagra: @thatsleepdoc

Dr. Shelby Harris is a clinical psychologist and behavioral sleep medicine specialist. She treats insomnia in women during perimenopause and menopause and is the author of "The Women's Guide to Overcoming Insomnia." Website: drshelbyharris.com Follow Dr. Harris: @SleepDocShelby

Hosted by Drs. Ayesha & Dean Sherzai Subscribe to The Synapse (free weekly newsletter): thebraindocs.com/newsletter Follow @TheBrainDocs on Instagram

Headlines warned us about microplastics in our brains. A chemist says the study may have been measuring brain fat instead.

In 2025, a study claiming microplastics accumulate in human brain tissue dominated our feeds. We covered it. Then Dr. Michelle Wong, a chemical scientist and science communicator, flagged a problem with the methodology.

So we went to the primary literature, read the critique, and brought in one of the first scientists to publicly challenge the findings: Dr. Oliver Jones, Professor of Analytical Chemistry at RMIT University in Melbourne.

In this episode, we unpack what went wrong with the measurement method, what it means for the broader microplastics conversation, and why being willing to say "I was wrong" is so vital for good science.

In this episode:

• How pyrolysis GC-MS works and why it can confuse plastic breakdown products with brain fat
• Why potassium hydroxide digestion creates soap, which also mimics plastic signatures
• The contamination problem: body bags, centrifuge tubes, plastic storage containers, and lab air
• Why 7 grams of microplastic per brain is more than what researchers find in raw sewage
• The Marfella study in The New England Journal of Medicine: microplastics in arterial plaques and why it also lacked blank controls
• How microplastics could enter the body: skin absorption, ingestion, and inhalation
• Why PM2.5 monitoring already captures the most relevant airborne microplastic exposure
• What the WHO, FDA, and European Food Safety Authority have concluded about microplastic harm
• What better microplastics research would actually look like
• Why the real lesson is about how we evaluate headlines, not just microplastics

Dr. Oliver Jones is Professor of Analytical Chemistry and Associate Dean of Biosciences and Food Technology at RMIT University in Melbourne. A Fellow of the Royal Society of Chemistry (FRSC) and the Royal Australian Chemical Institute (FRACI), he holds degrees from Imperial College London and Cambridge. He is one of only 118 scientists worldwide named to the IUPAC Periodic Table of Outstanding Younger Chemists. His research focuses on developing methods to measure environmental contaminants, including microplastics, and he was among the first scientists to publicly challenge the methodology of the viral "microplastics in the brain" study.

Follow Dr. Jones: @dr_oli_jones RMIT faculty page: rmit.edu.au/oliver-jones

Dr. Michelle Wong (Lab Muffin Beauty Science) first flagged the methodological concerns to us.

Hosted by Drs. Ayesha & Dean Sherzai Subscribe to The Synapse (free weekly newsletter): https://thebraindocs.com/newsletter Follow @TheBrainDocs on Instagram

Menopause hormone therapy and your brain: what the evidence says vs. what the algorithm is selling you.

Two-thirds of Alzheimer's patients are women. That statistic has fueled a social media narrative that hormone therapy can prevent dementia, but the current evidence doesn't support that claim. In this episode, Drs. Ayesha and Dean Sherzai sit down with OBGYN Dr. Jen Gunter and neuroscientist Dr. Sarah McKay to separate the science from the soundbites.

Your Brain On... Menopause Hormone Therapy [Season 7, Episode 1]

Get our FREE NEURO Plan Brain Health Playbook: https://thebraindocs.com/playbook

In this episode:

• Why menopause hormone therapy is the gold standard for hot flashes and night sweats but not a proven tool for dementia prevention
• The Women's Health Initiative: what it actually found, how the press conference distorted the findings, and what we've learned since
• Why "bioidentical hormones" is a marketing term, not a medical one, and what that means for the products being sold to you
• How the hypothalamus drives vasomotor symptoms and why sleep disruption may explain much of the cognitive fog women experience at midlife
• The high placebo response rate with hormone therapy and why dose escalation can mask a missed diagnosis
• Why the simplistic narrative of "women get more Alzheimer's, so it must be menopause, so give hormones" falls apart under scrutiny
• How over-testing, unregulated lab panels, and wearable hormone data can create more anxiety than answers
• The case for perimenopause as a life stage, not a disease, and why medicalizing normal midlife stress upholds harmful structures
• What the aging brain actually gains: vocabulary, emotional processing, wisdom, complex problem-solving, and the capacity to hold nuance
• 7 evidence-based actions you can take this week for your brain health, no prescription required
• Why the FDA's removal of the black box warning on hormone therapy was released without context and what happened next on social media
• The new neurokinin receptor antagonists and why they could change how we study the relationship between hot flashes and brain health

00:00 Intro

01:09 Why the menopause hormone therapy conversation matters

07:10 Dr. Jen Gunter: the dangerous dichotomy around MHT

10:20 The Women's Health Initiative, revisited

16:25 Who is menopause hormone therapy actually for?

18:20 The placebo response nobody talks about

22:33 When does perimenopause actually start?

26:00 Does MHT actually prevent dementia?

29:11 "Bioidentical" is not a medical term

36:27 The problem with unregulated hormone testing

41:08 How to advocate for yourself at the doctor

44:36 New drugs that could change menopause research

47:17 The pTau217 study and what it means for women on MHT

52:20 Dr. Sarah McKay: what happens in your brain during menopause

59:34 The oversimplified estrogen-Alzheimer's story

1:04:13 When social media primes your symptoms

1:11:18 What the aging brain actually gains

1:21:35 Grandmothers rule the world!

1:25:43 What MHT is actually good for

1:26:28 7 things to do for your brain

Dr. Jen Gunter is an OBGYN, pain medicine physician, New York Times columnist, and bestselling author of The Menopause Manifesto, The Vagina Bible, and Blood. She writes The Vajenda on Substack and is one of the most prominent voices challenging misinformation in women's health.

Dr. Sarah McKay is a neuroscientist, science communicator, and author of The Women's Brain Book. She is the founder of The Neuroscience Academy and Think Brain training programs.

References: North American Menopause Society 2022 Hormone Therapy Guidelines: menopause.org Australasian Menopause Society: menopause.org.au The Vajenda (Substack): jenssubstack.com

Get our FREE NEURO Plan Brain Health Playbook: https://thebraindocs.com/playbook

Hosted by Drs. Ayesha & Dean Sherzai. Subscribe to The Synapse (free weekly newsletter): thebraindocs.com/newsletter Follow @TheBrainDocs on Instagram

Most people think dementia starts with memory loss. But for millions, it actually begins decades earlier: in the blood vessels.

Long before someone forgets a name or misses an appointment, the brain is being quietly damaged by high blood pressure, cholesterol imbalance, poor sleep, inflammation, and chronic stress, day after day, year after year.

This kind of damage doesn't look dramatic. There's no big stroke, no clear warning sign. It happens slowly and silently, which is why it's so often missed until it's too late.

But here's the good news: vascular dementia is one of the most preventable and manageable forms of cognitive decline. When caught early, lifestyle changes and medical interventions can help slow the onset and manage the effects.

In this episode, we explore:

• What vascular dementia and vascular cognitive impairment are, and how they differ from Alzheimer's disease
• Why most dementia cases involve both vascular damage and neurodegenerative pathology (mixed dementia)
• How blood vessel damage begins in childhood and accumulates silently for decades
• The role of high blood pressure, cholesterol, diabetes, sleep disorders, and chronic stress in damaging brain vasculature
• Why slowed thinking, movement, and processing speed are hallmark signs of vascular cognitive decline
• The critical importance of the endothelium: the thin lining of blood vessels that controls brain health
• How lifestyle factors like nutrition, exercise, sleep, and stress management protect and repair vascular health
• Why managing blood pressure early is one of the most powerful interventions for long-term brain health (and why everyone should have a blood pressure monitor at home!)
• How vascular damage can be slowed, even in midlife
• Practical steps for prevention across the lifespan, from childhood through older adulthood

Our guest for this episode is DR. COLUMBUS BATISTE, a board-certified interventional cardiologist, an incredible science communicator, and author of 'Selfish: A Cardiologist's Guide to Healing a Broken Heart'. Dr. Batiste brings deep expertise on how cardiovascular health shapes brain health, and why protecting the endothelium (the inner lining of blood vessels) is foundational to longevity. His work emphasizes that all roads to longevity are paved by the heart, and what's good for the heart is good for the brain!

'Your Brain On…' is hosted by neurologists, scientists, and public health advocates Drs. Ayesha and Dean Sherzai.

SUPPORTED BY: NEURO World, a science-based brain health community designed to help you protect your brain long before problems begin. Learn more at https://neuro.world/

'Your Brain On… Vascular Dementia' • SEASON 6 • EPISODE 8

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LINKS

Dr. Columbus Batiste: https://drbatiste.com/

Instagram: @HeartHealthyDoc

Facebook: https://www.facebook.com/drbatiste

——— FOLLOW US

Join NEURO World: https://neuro.world/

Instagram: https://www.instagram.com/thebraindocs

YouTube: https://www.youtube.com/thebraindocs

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REFERENCES

Core Definitions & Diagnostic Framework

• Diagnostic and Statistical Manual of Mental Disorders (5th ed.) - American Psychiatric Publishing

• Vascular contributions to cognitive impairment and dementia - https://doi.org/10.1161/STR.0b013e3182299496

• Classifying neurocognitive disorders: The DSM-5 approach - https://doi.org/10.1038/nrneurol.2014.181

Epidemiology & Public Health Burden

• Neuropathological diagnosis of vascular cognitive impairment and vascular dementia with implications for Alzheimer's disease - https://doi.org/10.1007/s00401-016-1571-z

• Vascular dementia - https://doi.org/10.1016/S0140-6736(15)00463-8

• Risk reduction of cognitive decline and dementia: WHO guidelines - WHO Press

Small Vessel Disease & Subcortical Vascular Dementia

• Small vessel disease: Mechanisms and clinical implications - https://doi.org/10.1016/S1474-4422(19)30079-1

• Cerebral small vessel disease: From pathogenesis and clinical characteristics to therapeutic challenges - https://doi.org/10.1016/S1474-4422(10)70104-6

• The clinical importance of white matter hyperintensities on brain magnetic resonance imaging - https://doi.org/10.1136/bmj.c3666

Mixed Dementia & Alzheimer–Vascular Overlap

• Mixed brain pathologies account for most dementia cases in community-dwelling older persons - https://doi.org/10.1212/01.wnl.0000271090.28148.24

• Early role of vascular dysregulation on late-onset Alzheimer's disease - https://doi.org/10.1016/j.neurobiolaging.2016.04.009

• The pathobiology of vascular dementia - https://doi.org/10.1016/j.neuron.2013.10.008

Cerebral Amyloid Angiopathy (CAA)

• Cerebral amyloid angiopathy and Alzheimer disease—one peptide, two pathways - https://doi.org/10.1038/s41582-019-0281-2

• Emerging concepts in sporadic cerebral amyloid angiopathy - https://doi.org/10.1093/brain/awx047

Genetics, Inflammation, and Repair

• Apolipoprotein E controls cerebrovascular integrity via cyclophilin A - https://doi.org/10.1038/nature11087

• TREM2—A key player in microglial biology and Alzheimer disease - https://doi.org/10.1038/s41582-018-0072-1

Prevention & Vascular Risk Factors

• Dementia prevention, intervention, and care: 2020 report of the Lancet Commission - https://doi.org/10.1016/S0140-6736(20)30367-6

• Lifestyle interventions to prevent cognitive impairment, dementia and Alzheimer disease - https://doi.org/10.1038/s41582-018-0070-3

Further Reading

• The role of vascular risk factors in Alzheimer's disease - https://doi.org/10.1038/s41582-021-00530-4

Cold plunges are everywhere, and the way people talk about them, you'd think they're a miracle cure for your brain, body, and soul.

But in an age of algorithm-fueled evangelism, when a ritual becomes this ubiquitous and loud, we have to ask: how much of the buzz is backed by science… and how much is just marketing?

In this episode, we explore the neuroscience of cold exposure: what's real, what's overstated, and why this "discomfort" has become a billion-dollar industry.

We discuss:

• Why cold plunges went viral, and how wellness movements often devolve into identity-driven cultures
• The difference between cold exposure itself and the monetized "cold plunge movement"
• What constitutes a "cult" (and how pseudoscience forms around partial truths)
• The real physiological cold shock response
• Why the mental "high" after a plunge doesn't automatically equal long-term brain benefit
• The cardiovascular risks that rarely get discussed, especially for people with underlying heart disease
• What the research suggests about soreness, pain reduction, and muscle growth (including why cold immersion can blunt hypertrophy)
• The real story behind brown fat
• Who should avoid cold plunges altogether (asthma, arrhythmias, coronary disease, vascular conditions)

Joining us for this conversation is investigative journalist and bestselling author Scott Carney (What Doesn't Kill Us, The Wedge), who has spent years inside the cold exposure world, first as a skeptic, then as a believer, and eventually as a critic of the culture that formed around it. His work reveals what happens when discomfort becomes identity, and when unfounded "social media science" outruns real science.

Your Brain On... is hosted by neurologists, scientists, and public health advocates Drs. Ayesha and Dean Sherzai.

SUPPORTED BY: the 2026 NEURO World Retreat. A 5-day journey through science, nature, and community, on the California coastline: neuroworldretreat.com

Your Brain On... Cold Plunges • SEASON 6 • EPISODE 7

REFERENCES

Cold Water Immersion, Muscle Adaptation, and Recovery

Roberts, L. A., Raastad, T., Markworth, J. F., Figueiredo, V. C., Egner, I. M., Shield, A., Cameron-Smith, D., Coombes, J. S., & Peake, J. M. (2015). Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. Journal of Physiology, 593(18), 4285–4301. https://doi.org/10.1113/JP270570

Bleakley, C. M., McDonough, S. M., & MacAuley, D. C. (2004). The use of ice in the treatment of acute soft-tissue injury: A systematic review of randomized controlled trials. American Journal of Sports Medicine, 32(1), 251–261. https://doi.org/10.1177/0363546503260757

Leeder, J., Gissane, C., van Someren, K., Gregson, W., & Howatson, G. (2012). Cold water immersion and recovery from strenuous exercise: A meta-analysis. British Journal of Sports Medicine, 46(4), 233–240. https://doi.org/10.1136/bjsports-2011-090061

White, G. E., & Wells, G. D. (2013). Cold-water immersion and other forms of cryotherapy: Physiological changes potentially affecting recovery from high-intensity exercise. Sports Medicine, 43(8), 695–706. https://doi.org/10.1007/s40279-013-0055-8

Kellmann, M., Bertollo, M., Bosquet, L., Brink, M., Coutts, A. J., Duffield, R., Erlacher, D., Halson, S. L., Hecksteden, A., Heidari, J., Kölling, S., Meyer, T., Mujika, I., Robazza, C., Skorski, S., Venter, R., & Beckmann, J. (2018). Recovery and performance in sport: Consensus statement. International Journal of Sports Physiology and Performance, 13(2), 240–245. https://doi.org/10.1123/ijspp.2017-0759

Inflammation, Pain, and Perceived Recovery

Hohenauer, E., Taeymans, J., Baeyens, J. P., Clarys, P., & Clijsen, R. (2015). The effect of post-exercise cryotherapy on recovery characteristics: A systematic review and meta-analysis. PLoS ONE, 10(9), e0139028. https://doi.org/10.1371/journal.pone.0139028

Costello, J. T., Culligan, K., Selfe, J., & Donnelly, A. E. (2012). Muscle, skin and core temperature after –110°C cold air and 8°C water treatment. PLoS ONE, 7(11), e48190. https://doi.org/10.1371/journal.pone.0048190

Brown Adipose Tissue (BAT) – Human Imaging & Metabolism

van Marken Lichtenbelt, W. D., Vanhommerig, J. W., Smulders, N. M., Drossaerts, J. M., Kemerink, G. J., Bouvy, N. D., Schrauwen, P., & Teule, G. J. (2009). Cold-activated brown adipose tissue in healthy men. New England Journal of Medicine, 360(15), 1500–1508. https://doi.org/10.1056/NEJMoa0808718

Virtanen, K. A., Lidell, M. E., Orava, J., Heglind, M., Westergren, R., Niemi, T., Taittonen, M., Laine, J., Savisto, N. J., Enerbäck, S., & Nuutila, P. (2009). Functional brown adipose tissue in healthy adults. New England Journal of Medicine, 360(15), 1518–1525. https://doi.org/10.1056/NEJMoa0808949

Betz, M. J., & Enerbäck, S. (2015). Human brown adipose tissue: What we have learned so far. Diabetes, 64(7), 2352–2360. https://doi.org/10.2337/db15-0146

Autonomic Nervous System, HRV, and Cold Exposure

Mourot, L., Bouhaddi, M., Regnard, J., Tordi, N., & Rouillon, J. D. (2008). Cardiac autonomic control during short-term exposure to cold water in humans. European Journal of Applied Physiology, 104(3), 541–547. https://doi.org/10.1007/s00421-008-0810-3

Janský, L., Pospíšilová, D., Honzová, S., Uličný, B., Šrámek, P., Zeman, V., & Kamínková, J. (1996). Immune system of cold-exposed and cold-adapted humans. European Journal of Applied Physiology, 72(5–6), 445–450. https://doi.org/10.1007/BF00242276

Cardiovascular Stress and Cold Shock

Tipton, M. J., Collier, N., Massey, H., Corbett, J., & Harper, M. (2017). Cold water immersion: Kill or cure? Experimental Physiology, 102(11), 1335–1355. https://doi.org/10.1113/EP086283

Tipton, M. J., & Bradford, C. (2014). Cold water immersion and cold shock response. Extreme Physiology & Medicine, 3(1), 1–10. https://doi.org/10.1186/2046-7648-3-7

Whole-Body Cryotherapy (Distinct From Cold Plunges)

Costello, J. T., Baker, P. R., Minett, G. M., Bieuzen, F., Stewart, I. B., & Bleakley, C. (2015). Whole-body cryotherapy (extreme cold air exposure) for preventing and treating muscle soreness after exercise in adults. Cochrane Database of Systematic Reviews, 2015(9), CD010789. https://doi.org/10.1002/14651858.CD010789.pub2

LINKS

Scott Carney's website: https://www.scottcarney.com/

FOLLOW US

Join NEURO World: https://neuro.world/ Instagram: https://www.instagram.com/thebraindocs YouTube: https://www.youtube.com/thebraindocs More info and episodes: TheBrainDocs.com/Podcast

Around the start of 2026, a study sparked viral headlines claiming that cheese could reduce dementia risk.

But... nutrition science almost never works like this. One study can't "prove" a food is protective or harmful, and viral health claims often miss the most important details of research: how the data was gathered, what was actually measured, what variables were controlled for, and what it means in real life.

In this episode, we unpack what the 'viral cheese study' (PMID: 41406402) actually found, what it DOESN'T mean, and why critical thinking around nutrition headlines matters more than ever.

We discuss:

• Why viral food headlines are so persuasive (and so often misleading)

• What the cheese study REALLY reported

• The difference between correlation and causation in nutrition research

• Why long-term dietary recall data can be unreliable

• How bias (including our personal food preferences) shapes interpretation of research

• What "show me the data" really means in a world of clickbait science

• How to interpret food and brain health studies without falling into extremes

We also speak to Emily Sonestedt, research group leader and associate professor at Lund University, and one of the authors of the viral study.

"Your Brain On..." is hosted by neurologists, scientists, and public health advocates Drs. Ayesha and Dean Sherzai.

SUPPORTED BY: the 2026 NEURO World Retreat. A 5-day journey through science, nature, and community, on the California coastline: https://www.neuroworldretreat.com/

'Your Brain On... Cheese' • SEASON 6 • EPISODE 6

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LINKS

The study, 'High- and Low-Fat Dairy Consumption and Long-Term Risk of Dementia: Evidence From a 25-Year Prospective Cohort Study': https://pubmed.ncbi.nlm.nih.gov/41406402/

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FOLLOW US

Join NEURO World: https://neuro.world/

Instagram: https://www.instagram.com/thebraindocs

YouTube: https://www.youtube.com/thebraindocs

More info and episodes: TheBrainDocs.com/Podcast