LEVELS – A Whole New Level

Most of NextLevel starts with a measurement problem: we can see more biology than ever, but we still have to figure out what to do with it. Bioelectronic medicine flips that sequence. We already know how to send electrical signals into the nervous system to change biology, including an FDA-approved vagus nerve treatment for rheumatoid arthritis, even though we still can’t map or read most of the individual nerve fibers carrying those signals.

Mike Haney talks with Dr. Kevin Tracey, a pioneer of neuroimmunology and bioelectronic medicine, about what becomes possible when nerves become a therapeutic target. The opportunity is not simply vagus nerve stimulation, but learning which signals control specific organs, then building systems that can read and write them. That is still some distance away, and Tracey separates it from looser claims about vagal tone and vagus nerve hacks.

Free course: Improve your metabolic health
Get our free email course on how glucose, nutrition, exercise, sleep, and measurement can help you build habits that support better energy and long-term health: https://levels.link/wnl

What We Cover:
Why the vagus nerve is not one wire
How one minute a day became an FDA-approved rheumatoid arthritis treatment
Why a nerve target can be more precise than a drug
Why mapping the vagus fiber by fiber is only beginning
Why CRP and cytokines are not a true inflammation readout
What HRV, breathing, humming, and cold plunges can and cannot show

🎙️ About the Guest:
Dr. Kevin Tracey is a neurosurgeon, scientist, and President and CEO of the Feinstein Institutes for Medical Research. His work helped establish how the vagus nerve regulates inflammation and helped launch bioelectronic medicine. He is also co-founder of SetPoint Medical and author of The Great Nerve.

📍What Dr. Kevin Tracey & Mike Haney discussed:
00:00 - A nerve can treat one organ. A pill cannot
04:43 - The vagus nerve is 160,000 fibers, not one wire
07:53 - Why the first fiber-by-fiber map of the human vagus is only months old
10:29 - FDA-approved vagus nerve stimulation for rheumatoid arthritis
14:33 - Why one minute a day can quiet inflammation for 12 to 24 hours
17:39 - Why it took 30 years to get from the mouse finding to patients
31:53 - How one minute of current reaches millions of immune cells
41:19 - Why arthritis has a known mechanism and epilepsy and depression do not
49:16 - What single fibers could change in diabetes, the liver, the gut, and stroke recovery
52:59 - Why CRP and cytokine levels still fall short of a true readout
1:04:18 - Resting heart rate, not HRV, is the cleaner vagus signal
1:09:55 - Why deep breathing and humming are not vagus nerve stimulation
1:16:35 - A cold plunge is fight-or-flight first, vagus second
1:20:23 - The spleen signal he would measure if he could

🔗 Helpful Links:
The Great Nerve - Kevin J. Tracey (2025)
RESET-RA - Nature Medicine
SetPoint System - FDA
The inflammatory reflex - Nature (2002)
Vagus nerve stimulation in rheumatoid arthritis - PNAS (2016), early human study
Vagus nerve stimulation after stroke, paired with rehab - The Lancet (2021)

Watch the conversation: https://youtu.be/x_h6Dd_Ap_o
Find us on YouTube: https://youtube.com/levelshealth?sub_confirmation=1

📲 Connect:
Connect with Dr. Kevin Tracey at Feinstein Institutes for Medical Research

👋 Who we are:
Levels helps you understand your metabolic health with personalized data, expert guidance, and tools that connect your daily choices to measurable changes in your body. Our goal is to help you make better decisions about food, exercise, sleep, and long-term health.

Look for new shows every month on A Whole New Level, where we have in-depth conversations with thought leaders about metabolic health.

Most health decisions happen before the science is settled. A study points one way, another points somewhere else, experts disagree about what matters, and even strong population-level evidence may not tell you what will happen to you.

In this episode, Mike Haney talks with physician and economist Dr. Anupam Jena about how to make decisions under that kind of uncertainty. The goal isn’t to find a single hierarchy of evidence or a perfect source to trust. It’s to understand how much weight to put on any one piece of information, when personal experimentation can actually teach you something, and how the potential downside of an intervention should change the amount of evidence you demand before trying it.

Free course: Improve your metabolic health
Get our free email course on how glucose, nutrition, exercise, sleep, and measurement can help you build habits that support better energy and long-term health: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://levels.link/wnl⁠

What We Cover:
Why even a high-quality study should rarely change your mind by itself
Why a meta-analysis is only as useful as the studies that go into it
What randomized trials can establish, and where they can still fail to apply to real life
How to judge whether a study’s outcome is actually meaningful, not merely statistically significant
When N-of-1 experiments can help, and how they can fool you
A practical framework for deciding whether an intervention is worth trying: potential harm, quality of evidence, biological plausibility, and cost

🎙️ About the Guest:
Dr. Anupam Jena is the Joseph P. Newhouse Professor of Health Care Policy at Harvard Medical School, a physician at Massachusetts General Hospital, and an economist whose research uses natural experiments to uncover unexpected influences on health and medical care. He is also the host of Freakonomics, M.D. and co-author of Random Acts of Medicine.

📍What Dr. Anupam Jena & Mike Haney discussed:
04:04 - Why taxi and ambulance drivers die least often of Alzheimer's
09:20 - Why half of people still skip a free heart medication
13:02 - Why the headlines on coffee keep reversing
14:55 - Judge the study on its merits, not on who funded it
17:43 - Why even a high-quality study should rarely change your mind
23:04 - Why a cold plunge trial cannot separate the bath from the belief
26:19 - Why a meta-analysis is only as useful as the studies inside it
27:15 - What a randomized trial can establish, and where it still fails in real life
33:53 - The coin-flip test for whether a study shows cause and effect
36:25 - Absolute risk, relative risk, and what "significant" leaves out
43:06 - When an N-of-1 experiment can teach you what a trial cannot
46:02 - Getting better does not mean the experiment worked
53:55 - Harm, evidence, plausibility, cost: is it worth trying?

🔗 Helpful Links:
Dr. Anupam Jena — Harvard Medical School profile
Random Acts of Medicine — Anupam B. Jena & Christopher Worsham
Freakonomics, M.D. https://freakonomics.com/series/bapu
Alzheimer’s mortality among taxi and ambulance drivers (BMJ, 2024). Hypothesis-generating, not evidence that driving prevents Alzheimer’s: Read the BMJ study
Marathon road closures and cardiac mortality (NEJM, 2017): New England Journal of Medicine

Watch the conversation: https://youtu.be/k9XI7ym7iP8
Find us on YouTube: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://youtube.com/levelshealth?sub_confirmation=1⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠

📲 Connect:
Connect with Dr. Anupam Jena on https://x.com/AnupamBJena

👋 Who we are:
Levels helps you understand your metabolic health with personalized data, expert guidance, and tools that connect your daily choices to measurable changes in your body. Our goal is to help you make better decisions about food, exercise, sleep, and long-term health.

Look for new shows every month on A Whole New Level, where we have in-depth conversations with thought leaders about metabolic health.

Most medical imaging happens after a symptom, injury, or abnormal test gives a clinician a reason to look. But what changes if imaging becomes a more routine measurement, creating a record of the body before something goes wrong?
In this episode of Next Level, Mike Haney talks with Dr. Daniel Durand, chief medical officer at Prenuvo, about whole-body MRI as a test case for a broader shift from episodic medicine toward longitudinal health data. Whole-body MRI is controversial, and Durand is clearly an advocate. The conversation takes the skepticism seriously, then asks a larger question: as measurement gets cheaper, more frequent, and increasingly visible to patients themselves, how should medicine decide what is worth knowing?

Free course: Improve your metabolic health
Get our free email course on how glucose, nutrition, exercise, sleep, and measurement can help you build habits that support better energy and long-term health: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://levels.link/wnl⁠

What We Cover:
How X-rays, CT scans, ultrasound, and MRI differ, and why radiation matters when you start thinking about repeated imaging
What whole-body MRI sees well, and where CT, colonoscopy, or blood-based approaches may still be better
The concerns around incidental findings, overdiagnosis, anxiety, and unnecessary follow-up, and Durand’s response to them
What the current cancer-detection evidence for whole-body MRI does, and does not, establish
Why having prior scans could help distinguish a stable abnormality from something genuinely new
How faster scans and AI interpretation could eventually connect imaging with genomic, proteomic, and other health data

🎙️ About the Guest:
Dr. Daniel Durand is chief medical officer at Prenuvo and president of the Prenuvo Medical Group. He trained at Johns Hopkins, is board-certified in adult and pediatric radiology, and previously served as chief clinical officer and chief innovation officer at LifeBridge Health.

📍What Dr. Daniel Durand & Mike Haney discussed:
03:32 - Why imaging belongs in a series about continuous measurement
15:32 - Imaging 101: X-rays, CT, ultrasound, and MRI
28:57 - How AI is shortening MRI scan times
38:52 - Screening versus surveillance
40:26 - Which cancers whole-body MRI can miss
46:39 - The case against scanning healthy people
52:40 - What the cancer-detection data actually shows
54:39 - "We're all going to get a body scan"
1:03:31 - What would make routine imaging more useful?
1:11:49 - Building a baseline of the healthy body
1:17:43 - When AI can see more than a radiologist
1:21:28 - Is it better to know, even when you can't treat it?

🔗 Helpful Links:
Dr. Daniel Durand, Prenuvo: Prenuvo medical leadership
Meta-analysis behind the ~9,000 participants and ~1.6% detection figures. It notes limits, including incidental findings (European Radiology, 2026): PubMed
Prenuvo-associated study of 1,011 people, 2.2% confirmed cancer detection (Cancer Research/AACR, 2025): AACR abstract
Incidental findings in whole-body MRI and their psychosocial effects (European Journal of Radiology, 2021): PubMed
Prenuvo's research overview, including Polaris data (company-reported): Prenuvo clinical research

Watch the conversation: https://youtu.be/rFZVbzUPSaA
Find us on YouTube: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://youtube.com/levelshealth?sub_confirmation=1⁠⁠⁠⁠⁠⁠⁠⁠⁠

📲 Connect:
Connect with Dr. Daniel Durand at LinkedIn

👋 Who we are:
Levels helps you understand your metabolic health with personalized data, expert guidance, and tools that connect your daily choices to measurable changes in your body. Our goal is to help you make better decisions about food, exercise, sleep, and long-term health.

Look for new shows every month on A Whole New Level, where we have in-depth conversations with thought leaders about metabolic health.

Alcohol has spent the last 40 years bouncing between two health narratives: a little is good for your heart, or any amount is dangerous. The science doesn’t really support either slogan.
Dr. Tim Naimi has spent decades studying the health effects of alcohol and, just as importantly, why the research is so difficult to interpret. His read of the evidence is less dramatic but more useful: there’s no good reason to start drinking for your health, very low intake may carry little measurable added risk, and risk rises as consumption does. Understanding why earlier studies made moderate drinking look protective helps explain a lot of the whiplashing headlines.

Free course: Improve your metabolic health
Get our free email course on how glucose, nutrition, exercise, sleep, and measurement can help you build habits that support better energy and long-term health: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://levels.link/wnl⁠

What We Cover:
Why alcohol is a Group 1 carcinogen causally linked to at least seven cancers
Whether small amounts of alcohol really protect your heart
Why researchers still don’t have a definitive randomized trial of drinking and long-term health
How the “sick quitter” problem, selection bias, and confounding made moderate drinkers look healthier
Why two major recent reviews of alcohol and health produced such different headlines
How the risk changes with dose, including Naimi’s estimate of a 1 in 25 lifetime risk of an alcohol-caused death at 14 drinks per week
Why alcohol consumption is falling, and whether GLP-1 drugs could be contributing

🎙️ About the Guest:
Dr. Tim Naimi is a physician and alcohol epidemiologist who directs the Canadian Institute for Substance Use Research at the University of Victoria, where he is a professor in the Division of Medical Sciences.

📍What Dr. Tim Naimi & Mike Haney discussed:
00:45 — Why the science on alcohol is so confusing
05:48 — How alcohol damages DNA and raises cancer risk
09:43 — Is alcohol actually good for your heart?
14:22 — Why we still don't have a definitive randomized trial
20:30 — The "sick quitter" problem
24:56 — Selection bias and the problem with "healthy" moderate drinkers
29:35 — Why two major reports produced different headlines
31:37 — How alcohol risk changes as drinks per week increase
38:21 — Industry funding and conflicts of interest
46:15 — How much alcohol is too much?
49:48 — Why younger generations are drinking less
51:53 — Health consciousness, GLP-1s, and the decline in drinking

🔗 Helpful Links:
Alcohol Intake and Health Study: No Protective Effect at Low Levels, With Mortality Increasing to 1 in 25 at 14 Drinks Per Week (Journal of Studies on Alcohol and Drugs, 2026) Paper
Review of Evidence on Alcohol and Health (National Academies of Sciences, Engineering, and Medicine, 2025) Report
Association Between Daily Alcohol Intake and Risk of All-Cause Mortality: A Systematic Review and Meta-analyses (JAMA Network Open, 2023) Paper
Do “Moderate” Drinkers Have Reduced Mortality Risk? (Journal of Studies on Alcohol and Drugs, 2016) Paper
Alcohol Abstinence in Drinkers with Atrial Fibrillation (New England Journal of Medicine, 2020) Paper
Canada’s Guidance on Alcohol and Health (2023) Guidance and supporting research
Alcohol and Cancer (World Health Organization / IARC) WHO overview

Watch the conversation: https://youtu.be/8GNmcjPfg7U
Find us on YouTube: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://youtube.com/levelshealth?sub_confirmation=1⁠⁠⁠⁠⁠⁠⁠⁠

📲 Connect:
Connect with Dr. Tim Naimi at University of Victoria
👋 Who we are:
Levels helps you understand your metabolic health with personalized data, expert guidance, and tools that connect your daily choices to measurable changes in your body. Our goal is to help you make better decisions about food, exercise, sleep, and long-term health.

Look for new shows every month on A Whole New Level, where we have in-depth conversations with thought leaders about metabolic health.

From a single blood sample, new proteomic tools can now measure thousands of proteins at once. Dr. Tony Wyss-Coray’s lab is using that flood of data, together with machine learning, to build a much higher-resolution picture of what’s happening throughout the body and where someone’s health may be headed.

The early signals are striking. In one analysis of people who appeared healthy by conventional measures, every additional 4.1 years of estimated heart age was associated with nearly 2.5 times the risk of heart failure over the following 15 years. Wyss-Coray sees this kind of measurement eventually becoming a “health compass”: something that could show which parts of the body are changing fastest, then help track whether an intervention is actually moving them in the right direction.

Free course: Improve your metabolic health
Get our free email course on how glucose, nutrition, exercise, sleep, and measurement can help you build habits that support better energy and long-term health: ⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠⁠https://levels.link/wnl⁠

What We Cover:
How a drop of blood can now reveal information from thousands of proteins
Why aging appears to happen in waves rather than at a steady rate
Why one part of the body may age faster than the rest
What young-blood experiments in mice taught Wyss-Coray about proteins and brain aging
How the work is moving from whole organs down to individual cell types
Why the field’s biggest constraint may now be data collection rather than better AI

🎙️ About the Guest:
Dr. Tony Wyss-Coray is the D.H. Chen Distinguished Professor of Neurology and Neurological Sciences at Stanford University and director of the Phil and Penny Knight Initiative for Brain Resilience.

📍What Dr. Tony Wyss-Coray & Mike Haney discussed:
04:03 Proteins 101: the building blocks hiding information about your health
05:09 How one blood sample can measure thousands of proteins
09:07 Using machine learning to find patterns in the proteome
12:17 Can blood reveal what’s happening inside the brain?
13:11 What happened when young blood was given to old mice
19:45 Why aging may happen in waves rather than at a steady rate
29:24 How stable are protein measurements over time?
32:37 Can proteins predict disease years before it appears?
40:35 Why one part of your body may age faster than the rest
46:31 The missing test: does an intervention actually change the measurement?
51:04 Going from whole organs to individual cell types
54:10 Why more data, not better AI, is the current bottleneck
57:18 A future “health compass” for the body

🔗 Helpful Links:
Organ aging signatures in the plasma proteome track health and disease (Nature, 2023)Paper
The foundational organ-aging work discussed in the episode, using plasma proteins to estimate aging across 11 organs.
Plasma proteomic signatures of cellular aging predict human disease (Nature Medicine, 2026)Paper
The newer study extending the approach to more than 40 cell types using over 7,000 plasma proteins.
Undulating changes in human plasma proteome profiles across the lifespan (Nature Medicine, 2019)Paper

Young blood reverses age-related impairments in cognitive function and synaptic plasticity in mice (Nature Medicine, 2014)Paper

UK Biobank Research resource
The large longitudinal cohort used for much of the disease-prediction work discussed in the episode.

Watch the conversation: https://youtu.be/1dfMBAZiP8o
Find us on YouTube: ⁠⁠⁠⁠⁠⁠⁠⁠⁠https://youtube.com/levelshealth?sub_confirmation=1⁠⁠⁠⁠⁠⁠⁠⁠

📲 Connect:
Connect with Dr. Tony Wyss-Coray at Stanford

👋 Who we are:
Levels helps you understand your metabolic health with personalized data, expert guidance, and tools that connect your daily choices to measurable changes in your body. Our goal is to help you make better decisions about food, exercise, sleep, and long-term health.

Look for new shows every month on A Whole New Level, where we have in-depth conversations with thought leaders about metabolic health.