I've done carnivore once before. Three and a half months in 2025. I lost a lot of weight, felt better than I had in years, and then made the same mistake most people make when their protocol ends: I went back to eating whatever, drinking whenever, and watched the weight come back over the next nine months.
That's not a carnivore problem. That's an exit-strategy problem. And it's the entire reason I'm starting another block this week.
Let me lay out what I actually think about this diet. What the science says, what worked, what blew up in my face, and how I'm doing it differently this time. None of this is "carnivore is the best diet ever" energy. I don't believe that. I believe carnivore is a brilliant tool for a specific job, and a terrible religion to organize your life around.
The Thesis
Carnivore is a metabolic reset. Think of it like a financial audit for your body. You strip everything down to first principles, you get clarity on what's actually going on, you fix the structural problems, and then you exit back into normal life with better systems in place.
It's not designed to be permanent. It's designed to be intense, focused, and temporary. Two to three months once or twice a year. The other nine to ten months are where the actual lifestyle work happens.
That said, "the actual lifestyle work" is exactly where I've failed before. So this post is also a public commitment to fixing that part.
Why It Works (Without the Hype)
Four mechanisms are doing the heavy lifting on carnivore, and they all work together.
Insulin is the master switch
Most people don't think about insulin. They should. Insulin is the hormone that controls whether your body is storing energy or accessing stored energy. When insulin is high, fat is locked away. When insulin is low, the valve opens and your body burns through stored fuel.
A standard Western meal (pasta with sauce, bread on the side, a glass of wine) triggers something like 60 to 90 units of insulin. A full day of meat and eggs triggers maybe 15 to 20 units total. That's a massive structural difference. Carnivore drops insulin to the lowest functional level a non-fasting human can sustain.
For someone like me who's spent years cycling through periods of clean eating and periods of "eh, I'll start Monday," chronic low-grade insulin elevation is the background condition I'm trying to break.
Inflammation goes away
C-reactive protein is one of the cleanest markers of systemic inflammation. Mine was under 1.0 in 2020 when I was disciplined. By 2023, after a couple of off-diet years, it had climbed to 1.9. Not catastrophic. But measurable evidence that my body was running hotter than it should have been.
Carnivore tends to drop CRP by 30 to 50% within two weeks. The mechanism is obvious once you say it out loud: you simultaneously remove sugar, seed oils, processed food, alcohol, and grain. The four biggest drivers of chronic low-grade inflammation are all gone at once. The body gets to actually rest.
That inflammation you stop feeling is the background noise of modern life. The morning stiffness. The puffiness. The brain fog. The slow recovery from anything physical. You don't realize how much of that is dietary until it disappears.
Your brain switches fuel
The brain normally runs on about 120 grams of glucose a day. On carnivore, it switches over to running about 75% on ketones and 25% on glucose that your liver manufactures internally from protein. The technical name for that is gluconeogenesis, and it's the answer to "but doesn't your brain need carbs?" No. Your liver makes them.
Ketones produce less metabolic waste than glucose. The mental clarity isn't placebo. It's neurons running on a cleaner fuel source. Taste and smell sharpen too. Sensory receptors upregulate when you remove the constant noise of sugar and ultra-processed food.
Autophagy
This is the body's cellular cleanup crew. It identifies damaged cells, misfolded proteins, and dysfunctional mitochondria, and breaks them down for parts. The mechanisms were discovered by Yoshinori Ohsumi, who won the Nobel Prize for it in 2016. Autophagy is the actual biological process behind "fasting feels like it heals you," because it does.
It runs in the background every day you're in ketosis. Carnivore keeps you in deep ketosis without the willpower demands of straight water fasting.
Add to all of this: low insulin allows growth hormone to rise. Growth hormone preserves muscle during a caloric deficit. Cholesterol is the raw material for testosterone, and a meat-heavy diet supports its production. A lot of men report increased libido, confidence, and drive in week three or four. I had that effect last time. Made me a better entrepreneur. Also made me a slightly more intense husband for a few weeks, which Nikki tolerated with grace.
The Protocol I Actually Run
I'm 36, 195 centimeters tall, and I started this round at 120 kilos. I've done keto seven times, carnivore once before, and roughly ten ten-day water fasts over the years. I've been doing 18:6 intermittent fasting for about a decade and a half. The body knows the drill by now.
Here's what a normal day looks like.
Morning. Black coffee. A glass of water with half a teaspoon of Baja Gold salt stirred in. That's breakfast.
Fast until 13:00. I work from home running StudioFab, so the morning is for deep work. No food means no insulin response, no digestive load, no mid-morning crash.
Meal 1 at 13:00. 350 to 400 grams of gehakt (ground beef) cooked in its own fat, with four or five eggs scrambled in butter or ghee. I never drain the fat. The fat is the fuel.
Meal 2 at 17:30. Something cleaner and richer. Ribeye, duck breast with the skin on, bavette, or short ribs if I've had the slow cooker running. 400 to 500 grams of meat, five or six more eggs, more butter, more salt.
Done eating by 18:00. Bedtime around 22:00. That gives me a clean 19-hour overnight fasting window before the next meal.
I cycle: one OMAD day, two two-meal days. Keeps things flexible and keeps my body guessing.
The meat rotation matters less than people think. Ribeye is the king meal because of the fat-to-protein ratio. Short ribs are slow-cook days that give you collagen and glycine. Duck breast feels like a restaurant meal you happen to be making at home. Gehakt is the daily workhorse: cheap, fast, satisfying. Bavette is the quick lean option when you don't have time.
The non-negotiable cooking rule: ghee, butter, or beef tallow. Never seed oils. Save rendered duck fat for the next day's eggs. Salt everything generously, because on low insulin your kidneys dump sodium constantly.
The Electrolyte Reality
This is the single most underestimated thing on carnivore, and it's what makes most people quit in week one.
When insulin drops, your kidneys stop holding onto sodium and start flushing it out. If you don't replace it, you get the classic "keto flu": headache, fatigue, weakness, the feeling that the diet isn't working. The diet is working. You're just running on dangerously low sodium.
I aim for 5,000 to 7,000 milligrams of sodium per day. That sounds like a lot. It is a lot. Most people are running around on 2,000 to 3,000 and wondering why they feel terrible. The morning salt water is non-negotiable. If your salt water tastes sweet instead of salty, that's your body screaming at you that it's depleted.
Most commercial electrolyte pills are useless on carnivore. They're dosed for endurance athletes losing salt through sweat, not for someone whose kidneys are actively excreting it. Read the label. If a pill has 200 milligrams of sodium, you'd need to take 25 of them to hit the daily target.
What I Did Wrong Last Time
Now the personal part. The part that matters.
After my 3.5-month carnivore block in 2025, I exited rapidly. Fries one day, beer the next, a few weeks of "I earned this" thinking. Within a couple of months I started getting heart palpitations. Not painful. Just my heart skipping beats randomly through the day. Premature ventricular contractions. PVCs.
I saw a doctor. Heart was structurally fine. Benign. But it kept happening for months, and the doctor couldn't tell me why.
I figured it out only later, going through three rounds of bloodwork from 2020, 2023, and 2025 with Claude as a research assistant. Here's what happened.
Throughout my carnivore block I was taking an electrolyte supplement that contained 400 milligrams of potassium per dose, daily. I assumed I needed it. Everyone says you need it. My blood potassium at the end of the protocol was 4.6, which is already at the top of the normal range.
When I reintroduced carbs aggressively, insulin spiked. And insulin tells your kidneys to switch from excreting potassium to retaining it. So I had: already-elevated potassium, plus a sudden hormonal signal to retain more of it, plus continued supplementation that I hadn't thought to stop.
The result was cardiac electrical instability. Not dangerous. But unmistakable, and unsettling, and entirely avoidable.
The lesson: bloodwork matters. Don't blindly supplement just because the internet says to. And the exit from carnivore is at least as important as the entry, because that's when the hormonal switches flip in ways you're not paying attention to.
What I'm Supplementing This Time
Magnesium in multi-form (citrate, taurate, bisglycinate, malate). 200 milligrams before bed. Helps sleep, prevents cramps, and a meat-only diet is genuinely magnesium-light.
Vitamin D3. 2,000 to 4,000 IU daily. Friesland is at the same latitude as Edmonton. The sun is a rumor up here for six months a year.
Omega-3 fish oil. 2 to 3 grams daily. The beef in Dutch supermarkets is mostly grain-finished, which skews fatty acid ratios toward inflammatory. Fish oil rebalances that.
Salt. Enough to make a Dutch cardiologist nervous and a Saharan camel envious.
That's it. No potassium pills. No exotic stack. The food does the work.
The Exit Strategy
This is the part I had no plan for last time, and it cost me. This time it's written down and I'm following it.
Week 1 post-carnivore. Whole foods only, no alcohol. Berries, avocado, sweet potato added alongside meat. Stay in low-insulin territory and let the body re-orient gradually.
Week 2. Rice, root vegetables, more variety. Still no alcohol.
Week 3. Broader reintroduction. Still no alcohol.
Week 4. Alcohol slowly, mindfully, two-drink maximum nights only.
Magnesium and salt continue through the entire transition. The PVC window is highest during weeks one and two when hormonal signaling is re-orienting. Don't be a hero. Don't celebrate the end of carnivore by ordering a pizza and three beers.
The Honest Pattern
Here's what I have to be straight about with myself.
My pattern is: lose 15 to 20 kilos during a carnivore block, then drift back to standard eating, then gain most of it back over the following nine to ten months. Then run another block. This is weight cycling, and some research associates weight cycling with worse metabolic outcomes than just maintaining a higher weight.
The problem isn't carnivore. Carnivore works. The problem is that my baseline between protocols has been too low. Carnivore became a rescue mission instead of a tune-up.
The fix has to be permanent changes to the off-season. Not "kind of clean." Actually clean.
What I'm committing to this time:
Animal-based whole food baseline. 60 to 70% of calories from animal sources, year-round. Carbs as a condiment, not a staple. Berries, seasonal fruit, sweet potato, white rice when training hard. Not bread, not pasta, not crackers, not breakfast cereal, not any of it. Permanently eliminated: seed oils, refined sugar, wheat flour, ultra-processed anything. 80/20. Clean 80% of the time. Eat freely on social occasions and special days that matter. Don't pretend to be perfect, just don't be lazy. Weight guardrail at 110 kilos. If the scale crosses that line, I tighten up the same week. Not next month. That week.
If I run this for a year and don't need another rescue carnivore block in 2027, that's the real win.
Seed Oils
If you take one thing from this post and apply it permanently, take this one.
Industrial seed oils (soybean, canola, corn, sunflower, safflower, cottonseed, grapeseed, rice bran) are products of industrial chemistry that didn't exist in the human food supply before the early 1900s. They are extracted using hexane, a petroleum solvent, then bleached, then deodorized. The finished product is an extremely shelf-stable, extremely cheap fat that is also extremely high in omega-6 linoleic acid.
The human ratio of omega-6 to omega-3 evolved at somewhere between 1:1 and 3:1. The modern Western ratio is 15:1 to 25:1. Linoleic acid incorporates into your cell membranes, oxidizes, and creates inflammatory metabolites that hang around in your body fat for one to two years.
Each carnivore block helps purge stored seed oils. But the real fix is never adding them back. Restaurant fries, packaged snacks, salad dressings, mayonnaise, almost every product in the middle aisles of a supermarket: seed oils. Olive oil, butter, ghee, beef tallow, coconut oil, avocado oil for high heat. That's it.
This is the single most impactful permanent dietary change anyone reading this can make. Replace the seed oils in your kitchen. Pay attention at restaurants. Don't apologize for asking what something is cooked in.
The Indigenous Evidence
You can run the carnivore thought experiment two ways. From physiology, which is what I've been doing. Or from anthropology.
Look at every indigenous population that lived predominantly on animal foods for generations.
The Inuit, on a 90 to 95% animal diet, had near-zero heart disease, diabetes, and obesity until Western food showed up in the Arctic.
The Maasai, eating cattle blood, raw milk, and meat, had some of the lowest cholesterol and heart disease rates ever recorded despite massive animal fat intake.
The Mongolian steppe nomads conquered the largest land empire in human history on dried meat, blood, and mare's milk.
The Samburu of northern Kenya ate 400 grams of animal fat per day and showed cholesterol levels of 150 to 170 with virtually no heart disease.
The pattern repeats so cleanly it's hard to look away from. Every population that ate predominantly animal foods showed low rates of metabolic disease. Every population that transitioned to Western diets showed catastrophic health decline within a single generation.
I'm not arguing we should all be Inuit. I'm arguing the human species has thrived on meat-heavy diets for longer than recorded history, and the burden of proof is on the people calling that suddenly dangerous.
What Actually Happens (Week by Week)
If you do this, here's what to expect.
Week 1. Headaches that disappear with salt. Possible nausea if your meals are too lean. Increased thirst. Possible loose stools while bile production adjusts. A metallic taste confirming ketosis. Mental clarity starting to emerge.
Week 2. For experienced keto dieters, adaptation is complete. Sleep stabilizes and quality dramatically improves. Energy becomes steady. No afternoon crashes. Appetite self-regulates. Taste buds sharpen. Meat tastes sweeter. Eggs taste richer. Skin tans faster and deeper than usual.
Weeks 3 and 4. Visible fat loss, face changes first. Plateaus happen, ignore them. Brief low frustration tolerance as serotonin re-orients. Sleep needs drop slightly but quality is higher. Joint pain and stiffness and puffiness fade.
Week 5 and on. Autopilot. Food becomes fuel. The relationship with food fundamentally changes. Energy and clarity become the new normal. The carnivore "high" softens into a steady baseline.
Alcohol on Carnivore
Honest take: alcohol on ketosis hits harder. Two drinks feel like four or five. Tolerance drops fast.
If you do drink, gin or vodka with sparkling water and lime is your friend. Zero carbs, zero sugar. Tonic water is loaded with sugar. Beer destroys ketosis. Wine isn't terrible but it's not great. Cocktails with syrups are a no.
But here's the bigger truth. Alcohol stops fat burning while your liver processes it, disrupts REM sleep by 20 to 40% even at two drinks, and the morning after, cravings return and energy tanks and your step count drops.
My personal rule for this block: two or three planned social events over the entire protocol. Planned drinks are manageable. Unplanned "I just had a couple" nights are how the whole thing unravels.
The Data So Far
First 12 days of this round.
Weight: 120 to 113.8 kilos. That's mostly water and inflammation early on. Real fat loss only really kicks in around week three.
Sleep: my Garmin score went from volatile, swinging between Low and Very High, to consistently High. Sleep is the single best leading indicator that the protocol is working.
Steps: hitting the 12,000 daily target. Last year's average was 9,220. Walking is non-negotiable in this protocol.
Target by June 22: 106 to 108 kilos. Target by end of August, after a second block: 100 kilos.
Bloodwork trend across 2020, 2023, and 2025 panels:
TSH 3.5, then 4.21, then 1.5. Thyroid dramatically improved with disciplined diet.
CRP under 1.0, then 1.9, with 2025 pending. Inflammation rises during off-diet years.
Kidneys: perfect across all three panels despite my industrial salt intake. The "all that salt is killing your kidneys" worry is mostly outdated medicine.
The Real Reason I'm Doing This Again
I probably never in my life felt as good as I felt on carnivore.
Steady energy. Clean head. Stable mood. Quick recovery from training. Sleep that actually restored me. A relationship with food that felt simple instead of fraught. Confidence at home, at work, with myself.
I let that slip away once. I'm not interested in letting it slip away again.
The carnivore block is two months of effort. The real challenge is the nine months between. That's where the actual work lives. I'm writing this in part to hold myself to it.
If you're considering carnivore, my honest advice. Don't do it as a lifestyle. Do it as a tool. Two or three months, deliberate and disciplined. Then exit gradually, hold a high baseline, and run it again next year if you need to. The first time you do it, you'll feel like you discovered something. By the third time, you'll realize the discovery isn't carnivore. It's what carnivore reveals about how good your body is allowed to feel when you stop messing with it.
I'll write a follow-up in three months with the end-of-block numbers and what I learned. If the exit goes well this time, the post after that will be the most important one.
— Fab