Knife Down
"Knife Down" is what a surgeon says in the OR when she puts her scalpel down so no one gets hurt — and it’s the mission here: put the knife down, long before anyone needs to use it.
Knife Down is a podcast about how to actually invest in your health so you can live longer, stronger, and with less time in doctors’ offices. The core focus is the world’s leading cause of death—cardiovascular disease—and what to do about it before it shows up as a catastrophe.
Hosted by a vascular surgeon on a mission to put herself out of business, the show translates cutting-edge science on prevention, metabolic health, and longevity into real-world strategies you can use in clinic or at your kitchen table. Expect evidence, nuance, and zero wellness hype—plus the occasional dark joke about the state of modern medicine.
Episodes
42 episodes
Can You Take Too Much Vitamin K2? Vascular Surgeon Explains
Can you take too much vitamin K2? In this video, I answer the most common follow-up questions about vitamin K2, including dose, safety, testing, interactions, and whether more is actually better.Here's the original video on the K2 clini...
Vitamin K Slows Coronary Calcium: NEW Netherlands Study
Can vitamin K2 slow coronary artery calcium? A new JAMA Cardiology randomized trial found that MK-7 may reduce CAC progression over 2 years — but the real story is more complicated.TL;DR: In this randomized trial, people with symptomati...
Surgery for Alzheimer's...Is It Real? (and other questions)
In this Q&A session, Dr. Lily Johnston dives into complex viewer questions regarding cardiovascular health and emerging medical research. She covers the impact of hormone therapies on LP(a), the nuances of managing cholesterol after a heart...
99% of heart attacks had a warning. Your doctor called it "normal."
Can you have a heart attack with “normal” labs and no warning signs? Or are we missing the warning signs because our thresholds are too late and our prevention model is too reactive?Today I react to a fascinating video from
Can THIS Supplement Prevent Heart Disease? Surgeon Reacts to Dr Boz
Are omega-3s really the #1 supplement for heart disease prevention? In this reaction to Dr. Boz, I break down the nuance: atrial fibrillation risk, rancid oils, DHA vs EPA, heavy metal testing, delivery forms, omega level testing, and why small...
AMA #2: Why a 'Perfect' LDL Won't Save You--Plaque, Statins & Metabolic Health
A live, unfiltered Ask Me Anything on preventive cardiology and metabolic health — recorded on about three hours of sleep after a night in the OR, which tends to make me a little more candid than usual.We cover the questions you actuall...
The Biggest Walking Mistake I See: PAD Q&A
Peripheral artery disease Q&A — including one of the biggest mistakes people make when trying to “walk off” PAD symptoms.In this video, we break down:• Why erectile dysfunction is actually a sign of vascular disease• What an...
Got APOE4? A Vascular Surgeon’s EXACT Plan to Protect Your Brain
Got APOE4? Here’s the exact prevention strategy I would use to protect my own brain if I carried this gene.In this video, I walk through the major modifiable dementia risk factors identified by the Lancet Commission — and how I would ac...
Brain Health Q&A: ApoB, APOE2, pTau217 & More
What's the optimal ApoB level to reduce Alzheimer’s risk? Is lifestyle or genetics more important? And what does a pTau217 result actually mean for your brain health?In this Brain Health Q&A, I answer your questions about ApoB, APOE...
Half of Alzheimer's Patients Carry APOE4 - You Don't Have to Be One of Them
If you've been told APOE4 means you're destined for Alzheimer's, the science says something very different.As a vascular surgeon who has spent years treating the end-stages of preventable disease, I want to give you a clearer picture of...
Can Low LDL Cause Dementia? Your Questions Answered
Does lowering LDL cholesterol cause dementia? And how much dementia is actually “vascular” dementia versus Alzheimer’s disease?In this video, I’m answering two viewer questions about dementia, vascular risk, statins, LDL cholesterol, an...
LDL Study Q&A: kidney damage, NNT, and funding sources
You asked 349 questions about my LDL video. I'm answering the ones that matter most — including who paid for the study.Last week I broke down the LDL cholesterol trial. The comments flooded in — and several of you asked exactly the righ...
Is Ezetimibe the Secret to Preventing Dementia? Surgeon Reacts to Nick Norwitz MDPhD
A common cholesterol drug might protect your brain from Alzheimer's — but I read the actual study, and there's a red flag nobody is talking about.Nick Norwitz covered this story. I went further — I pulled the original paper published in...
Is Lower LDL Actually Better? New Research Has an Answer
Is lower LDL cholesterol actually better for your heart? In this video, I break down the brand-new results from the EZ-Pave study to answer the question that keeps my patients up at night: How low should your cholesterol really go?
The Truth About Aspirin and Heart Attack Prevention
I've seen daily aspirin save lives from heart attack — and cause fatal bleeds. As a vascular surgeon, here's my honest take on heart health.The answer isn't yes or no — it depends entirely on who you are.In this video I break do...
Ask Me (Almost) Anything With Dr Johnston | Live Q&A
We hit all the high points today! Nutrition, exercise, lipids, dental health, hormones, and more. We had amazing participation and it was wonderful to have a chance to interact with everyone in real time. Thanks SO much for taking some of your ...
Can You Unclog Arteries? A Vascular Surgeon Reacts to Dr Kevin Ham
Plaque reversal is one of the most debated topics in preventive cardiology, so in this video I react to Dr. Kevin Ham’s CAST protocol for plaque reversal: Causes, Adding Cures, Strengthening the Body, and Training the Mind and Body.Over...
I'm a Vascular Surgeon — Stop Getting Repeat CAC Scans. Here's Why
If you’ve had a positive calcium score (CAC score), you’ve probably asked the obvious next question: when should I repeat it?In this video, I explain why I generally do not order another calcium score if the first one is positive—and wh...
Is Your Candle Slowly Poisoning You? Vascular Surgeon Reacts to Joe Rogan
Joe Rogan got half a million people talking about what's happening inside their blood vessels. As a vascular surgeon, I've spent my career trying to do exactly that. So when a celebrity does it for me, I pay attention (and thank my lucky stars ...
GLP-1 Drugs Cut Heart Attack Risk — And It Has Nothing to Do With Weight
SELECT trial explained: does semaglutide reduce cardiovascular risk because of weight loss, or is something else going on? In this video, I break down the SELECT trial and the follow-up analysis examining whether the cardiovascular benefit of s...
What We Get Wrong About Poor Circulation (with Vascular Surgeon Dr. Jackie Majors)
When people hear “poor circulation,” they often assume the answer is a procedure. Not so fast. In this episode of Knife Down, Dr. Jacqueline Majors and I talk about when opening a blocked artery helps, when it backfires, and why the real work o...
They Don’t Want You Well. They Want You Worried.
Are supplements safe? Not automatically. In this video, I explain why supplements are really drugs, why the industry has so little oversight, which products worry me most, and how I think about using supplements more safely in real life.
When "Healthy" Is a Lie: @DrFordBrewer on Insulin Resistance, Hidden Plaque & His Prevention Pivot
• Feeling “healthy” is not a screening test. In this episode, Dr. Ford Brewer ( @DrFordBrewer ) tells the origin story: an ER doc who believed he was doing ...
The Blood Pressure Myth That Won't Die: A Vascular Surgeon Reacts to @DrAlexWibberley
Hypertension isn’t a mystery. It’s physics. And it’s quietly remodeling your arteries while you’re out here arguing with your salt shaker.In this reaction to @DrAlexWibberly, I’m mostly nodding along—because he nails the big idea: blood...
HIIT vs Heart Plaque: Randomized Trial Deep Dive
In this research report deep dive, I walk through a randomized trial that asked a very specific, very modern question: can high-intensity interval training (HIIT) measurably change coronary atherosclerotic plaque—not just your VO₂ max?W...