The Metabolic Theory of Cancer Explained: Why I Chose a Carnivore Diet Alongside Conventional Cancer Treatment

I Never Expected to Become a Student of Cancer

When I was diagnosed with stage four cancer, I thought my role was simple. Show up for appointments. Receive treatment. Hope for the best.

Instead, I found myself spending thousands of hours reading medical journals, watching lectures from researchers around the world, and trying to understand one question that kept coming back to me.

Why do cancer cells behave so differently from healthy cells?

The more I learned, the more I realized there were two very different ways of looking at cancer.

The first is familiar to most of us. Genetic mutations accumulate. Those mutations let cells grow out of control. Treatments are designed to destroy those abnormal cells while protecting healthy tissue.

Then I discovered another way of looking at cancer.

It is called the metabolic theory of cancer.

Rather than asking what mutations caused the cancer, it asks a different question.

What if abnormal cellular metabolism is one of the driving forces behind cancer growth?

I did not become skeptical of conventional medicine. I did not abandon my oncologist. I did not stop treatment. I simply wanted to understand everything I could about the disease trying to take my life.

That search changed how I ate, how I exercised, which supplements I chose, and how I monitored my lab work. Eventually it led me to adopt a carnivore diet as one part of a much larger strategy.

This Is Not Medical Advice

I am not a physician. I am not giving medical advice. Every cancer diagnosis is different, and every treatment plan should be discussed with qualified medical professionals who understand your specific situation.

What I am sharing is my own research and my own experience after being diagnosed with metastatic HPV positive, p16 positive oropharyngeal squamous cell carcinoma.

Some of what you’ll read is widely accepted science. Some is an active area of research. Some remains controversial. I believe readers deserve to know the difference.

Why I Started Looking Beyond Standard Treatment

My treatment has included surgery, radiation, chemotherapy, and immunotherapy. I am grateful those treatments were available, and I believe they have helped keep me alive.

But I also asked myself another question. Was there anything else I could reasonably do to improve my odds? Not to replace conventional treatment, but to support my body while I received it.

Could improving my metabolic health matter? Blood sugar, insulin, inflammation, muscle mass, vitamin D, exercise, sleep, sunlight, stress? Those questions led me to the work of Dr. Otto Warburg, whose discoveries nearly one hundred years ago still influence cancer research today. Metabolism, it turns out, is not a fringe topic. It is one of the most actively studied areas in modern oncology.

Why This Article Is Different

There are countless articles online about the metabolic theory of cancer, written by researchers, physicians, and people selling a diet or supplement.

This one is written by someone who has lived with stage four cancer. Someone who has sat in infusion chairs, waited on CT scan results, and known what scanxiety feels like.

Over the past several years, I have read hundreds of scientific papers on cancer metabolism, ketogenic and carnivore diets, fasting, glucose regulation, vitamin D, exercise, inflammation, and integrative oncology, and changed my own lifestyle based on that research while continuing to work closely with my oncology team.

Was the carnivore diet the only reason my health improved? I cannot honestly say that. My progress has come from surgery, radiation, chemotherapy, immunotherapy, nutrition, exercise, and other supportive therapies together. No single piece deserves all the credit. But together, they became the strategy I chose.

If you’d like to explore this topic in greater depth, I invite you to read my memoir, Still Here: How Faith, Food, and Family Beat Stage Four Cancer. In addition to sharing my personal journey, I include my clinical timeline, CT scan results, laboratory data, treatment decisions, and the integrative strategies I chose alongside conventional medicine. The book also references many of the leading scientific studies that shaped my research and helped me become an informed participant in my own care. If you’re searching for hope grounded in both personal experience and scientific evidence, I believe you’ll find it to be a valuable resource.

What Is the Metabolic Theory of Cancer?

Before my diagnosis, I assumed cancer was simply a disease of bad genes: mutations form tumors, doctors treat them, and hopefully the treatments work.

Then I started reading, and realized there is another layer. That layer is metabolism.

Every Cell Needs Energy

Every cell in your body needs energy, called ATP, to survive. Healthy cells make ATP mainly through mitochondria, the “powerhouse of the cell,” combining nutrients from food with oxygen.

Healthy cells are also remarkably flexible. They can run on glucose from carbohydrates, on ketones the liver produces when carbs are scarce, or on stored fat during a fast. This metabolic flexibility is part of how humans survived thousands of years of feast and famine.

Cancer Cells Are Different

Cancer cells need enormous amounts of energy to grow and divide rapidly, but many don’t rely primarily on healthy mitochondria. Instead, they lean heavily on glycolysis, breaking down glucose, even when oxygen is plentiful. Healthy cells usually reserve that process for emergencies like intense exercise. Cancer cells often do it constantly.

That inefficiency puzzled researchers nearly a century ago. It puzzled me too.

Enter Dr. Otto Warburg

In the 1920s, Dr. Otto Warburg discovered that many cancer cells consume glucose at extremely high rates and convert much of it into lactate, even with oxygen readily available. This became known as the Warburg Effect and earned him the 1931 Nobel Prize in Physiology or Medicine. Nearly a century later, researchers are still studying what it means for treatment.

Two Different Ways of Looking at Cancer

The genetic theory says mutations disrupt the normal controls on cell growth and division until cancer develops. There is overwhelming evidence for this.

The metabolic theory asks whether damaged metabolism and dysfunctional mitochondria are also driving forces, not just a byproduct of cancer. These ideas are not mutually exclusive. Many scientists now believe genetics and metabolism influence each other in ways we are only beginning to understand.

I wasn’t looking for an alternative to oncology. I was looking for every reasonable advantage. That doesn’t mean every claim I found online was true. I quickly learned to be skeptical of anyone claiming a miracle cure every oncologist was supposedly ignoring, and I kept reading until I found the original research. Science advances one carefully designed study at a time, and it is rarely black and white.

Could improving my metabolic health work alongside conventional treatment rather than compete with it? That question eventually led me to study blood sugar, insulin, ketosis, fasting, and the carnivore diet. But first I wanted to answer something more basic.

Does Sugar Feed Cancer?

This is probably the most debated and most misunderstood question in cancer nutrition. Search online and you’ll find two opposite answers: sugar has nothing to do with cancer, or eliminating sugar will stop tumors. Neither tells the whole story.

Every Cell in Your Body Uses Glucose

Healthy cells use glucose too, including your brain and your immune system. Even if you never eat sugar again, your liver makes glucose from protein and fat through gluconeogenesis. You cannot “starve” your body of glucose. It isn’t possible. So the claim that simply cutting sugar will kill cancer doesn’t hold up biologically.

So Why Do Researchers Talk About Sugar and Cancer?

Because cancer cells often consume glucose at unusually high rates. Doctors use this fact every day: a PET scan injects a radioactive form of glucose, and rapidly growing cancer cells frequently absorb far more of it than healthy tissue. In a sense, the cancer helps reveal itself, which traces back to the Warburg Effect. That doesn’t prove sugar causes cancer, but it explains why researchers keep studying cancer metabolism.

Glucose Is Only Part of the Story

Insulin kept appearing throughout my research. It’s more than a blood sugar hormone; it’s a powerful growth signal telling the body to store energy and build tissue. Researchers are studying whether chronically elevated insulin may influence the growth of some cancers. That doesn’t mean insulin causes cancer. It means insulin is part of an incredibly complex system worth paying attention to.

Before adopting a carnivore diet, my blood sugar often drifted into the prediabetic range. Afterward, it became remarkably stable. That didn’t prove I was affecting my cancer, but it improved something I could actually measure: healthy blood sugar, reduced visceral fat, adequate protein, preserved muscle, lower inflammation, better metabolic flexibility. Those goals make sense regardless of what future research shows.

Why I Chose the Carnivore Diet

I didn’t choose it believing it would cure my cancer. I chose it because it solved several problems at once. It dramatically reduced carbohydrates, stabilized my blood sugar, lowered insulin exposure, made it easy to eat the protein my body needed, removed highly processed food, and simplified eating during treatment.

Cancer takes away so much control. You can’t control your diagnosis, your scan results, or how your body responds to treatment. But you can control what you put on your plate. For me, that mattered.

What Does the Research Actually Say?

Researchers generally agree that many cancer cells consume large amounts of glucose, and that obesity, insulin resistance, and poor metabolic health raise the risk of several cancers. Where debate continues is whether intentionally restricting carbohydrates or maintaining ketosis improves outcomes once cancer has already developed. Early studies are mixed, and different cancers, and different patients with the same cancer, respond differently. Hope should always be balanced with humility.

Can Cancer Cells Use Ketones?

The basic idea behind a ketogenic diet sounds simple: lower glucose and insulin, force the body to burn fat and produce ketones, and let healthy cells adapt while cancer cells struggle. It isn’t that simple. Some cancer cells appear to have difficulty using ketones efficiently. Others adapt and use them just fine. Cancer changes its own metabolism when its usual fuel becomes scarce, which is part of why it is so hard to treat.

What Are Ketones?

Ketones, mainly beta hydroxybutyrate, acetoacetate, and acetone, are produced by the liver when carbohydrate intake is very low or during fasting. Healthy cells, including in the brain and heart, can shift to using them. This shift, nutritional ketosis, is a regulated physiological state, not the dangerous diabetic ketoacidosis associated with uncontrolled diabetes.

Why Some Researchers Believe Ketones May Disadvantage Cancer

Using ketones efficiently requires functioning mitochondria. Many cancer cells have altered mitochondrial function and depend heavily on glycolysis, so lowering glucose while raising ketones could theoretically create an energy disadvantage for a tumor while healthy cells continue adapting normally. Some lab and animal studies support this, along with effects on oxidative stress, inflammation, and treatment response. That’s encouraging, but most of this evidence still comes from cells in dishes or animals, not proof of what happens in every human being. (PMC)

Some Cancer Cells Can Use Ketones

This part often gets left out. Some tumors have functioning mitochondria and the enzymes needed to break down ketones, and use ketones, fatty acids, lactate, or glutamine when glucose is scarce. Researchers have observed this in certain breast, liver, and brain cancer models, and a 2025 study identified a pathway by which some cancer cells use beta hydroxybutyrate for growth. (PMC) Ketones don’t always feed cancer, but there’s no honest one-sentence answer. Cancer isn’t one disease. Genetics, mitochondria, surrounding tissue, and available fuel all vary from tumor to tumor, which is why changing one nutrient doesn’t always produce a predictable result.

A tumor also doesn’t exist in isolation. It sits inside a tumor microenvironment of blood vessels, immune cells, and signaling molecules that can supply lactate or ketones, or compete with immune cells for nutrients.

Ketones May Do More Than Provide Energy

Beta hydroxybutyrate also acts as a signaling molecule, potentially influencing inflammation, gene expression, and immune function. Some animal research suggests ketosis may improve responses to certain immunotherapies in specific models, which caught my attention since immunotherapy is part of my own treatment. But a mouse study identifies a possibility. It doesn’t promise a result for a person in an infusion chair.

Ketosis Is Not the Same as a Carnivore Diet

A ketogenic diet is built around very high fat and very low carbohydrates. A carnivore diet eliminates plant foods and centers on meat, eggs, fish, and animal products, and depending on protein intake may or may not produce consistently high ketones. My diet has been high in protein because preserving weight and muscle during treatment was a priority, so my approach isn’t identical to a medical ketogenic diet. I chose carnivore because it removed sugar, refined carbs, seed oils, and processed food; stabilized my blood glucose; delivered the protein I needed; and gave me a workable way to eat when swallowing and appetite were difficult. Ketosis was part of my thinking. It wasn’t the whole reason.

I have seen people become obsessed with ketone meters, assuming a higher number means a stronger anticancer effect. We don’t have evidence for that. A ketone reading can confirm you’re in nutritional ketosis. It cannot tell you whether a tumor is shrinking, and it cannot replace imaging, blood work, or your oncologist.

Human Evidence Is Still Limited

Medically supervised ketogenic diets are feasible for some cancer patients, but maintaining them during chemotherapy, radiation, or advanced disease is difficult, and nausea, swallowing problems, and unintentional weight loss can make any restrictive diet dangerous for the wrong patient. Research hasn’t established that a ketogenic diet alone consistently shrinks tumors or extends survival across cancer types. Many trials are small, some lack control groups, and definitions of ketosis vary between studies. The evidence is developing. It is not settled. (PubMed)

Weight loss deserves special attention here. Many cancer patients already struggle with appetite, swallowing, nausea, or taste changes, and a restrictive diet can make that worse. Losing muscle during treatment is not a victory; it affects strength, balance, immune function, and the ability to tolerate treatment. Radiation and surgery damaged my own ability to swallow, so I eat slowly, use techniques from speech therapy, and focus hard on protein. A diet that looks perfect on paper is useless if a patient can’t eat enough to survive treatment.

What I Believe the Evidence Supports

Many cancers have altered metabolism and consume large amounts of glucose. Some cancer cells struggle to use ketones efficiently; others adapt and use them well. Ketogenic approaches may have value alongside conventional treatment, particularly when they improve metabolic health, but they are not established cures and should not replace surgery, radiation, chemotherapy, or immunotherapy.

I chose a low carbohydrate carnivore diet because I believed the potential benefits justified trying it, and because I could monitor the results: blood sugar, weight, kidney function, liver enzymes, calcium, blood counts, all while continuing conventional treatment and imaging. I didn’t need the science to be perfect before improving my metabolic health. I did need to stay honest about what the science could and could not prove.

The Most Important Decision I Had to Make

In June 2025, the cancer spread to my lungs. My oncologist recommended Keytruda combined with chemotherapy.

I had already been through chemotherapy once. It saved my life, but it also left me with permanent neuropathy in my feet. The thought of losing function in my hands too, buttoning a shirt, typing, holding a coffee cup, terrified me more than the fight itself. I had also previously had a serious immune related reaction to immunotherapy that affected my thyroid, so restarting it wasn’t a decision I took lightly either.

I researched, prayed, and talked with my family. In the end, I chose to move forward with Keytruda but declined additional chemotherapy, weighing the potential benefits against the risks my body had already endured.

At the same time, I decided not to rely on one treatment alone. I committed to improving my metabolic health: a strict carnivore diet, high dose IV Vitamin C twice weekly, carefully monitored high vitamin D levels, daily sunshine, strength training, and continued study of the science. None of it replaced my oncologist’s care. It complemented it.

My Complete Metabolic Strategy

People often ask what my cancer protocol is, hoping for one simple answer. There isn’t one.

Conventional treatment always came first, led by my oncology team: surgery, radiation, chemotherapy, and Keytruda when the cancer spread. Everything else was meant to support my body while treatment did its job, not replace it.

Nutrition became my foundation. A strict carnivore diet for stable blood sugar, lower insulin, no processed food, and enough protein to preserve muscle.

Vitamin D became a priority. Many cancer patients run low, and researchers continue studying its role in immune function and outcomes. I worked with my physicians and monitored blood levels rather than guessing.

I began high dose IV Vitamin C, which reaches blood concentrations oral supplements cannot achieve. Some research suggests it may improve quality of life or reduce side effects; other research explores whether it may enhance certain treatments. The evidence is still developing, but it was biologically plausible, safe under medical supervision, and worth trying alongside conventional care.

Sunshine became part of my daily routine, made easier by the move from Minnesota to Florida. It supported my vitamin D strategy, and it reminded me that life continued beyond appointments and scans.

Exercise was not optional, even on the days I didn’t feel like it. Not to build bigger muscles, but to keep the ones I had.

I kept learning, because medicine never stands still, and I stayed willing to change my mind if stronger evidence called for it.

And faith held everything together. I prayed before appointments, after scans, while waiting for biopsy results, sometimes with confidence and sometimes through fear. Faith didn’t remove the uncertainty. It gave me the strength to live with it.

I honestly don’t know which piece mattered most. Keytruda, the diet, vitamin D, IV vitamin C, exercise, sunlight, prayer. I don’t think anyone can say for certain. What I know is that I chose to attack this disease from every reasonable angle available to me, and I have never regretted that decision.

What the Research Says Today

Cancer metabolism has become one of the fastest growing areas in oncology. Can improving metabolic health influence progression? Can lowering insulin help outcomes? Can ketosis make some treatments more effective? These are no longer fringe questions; they are legitimate areas of investigation, and respected cancer centers are studying them because the questions are worth asking, not because the answers are settled.

That said, if someone tells you the science is settled, be cautious. Some trials show promising results, others show little benefit. Some cancers respond better than others. Some patients tolerate ketogenic diets well; others cannot maintain adequate nutrition on them. I have learned to be comfortable saying, “I don’t know.”

Large clinical trials in this area are genuinely hard to run. Every patient has a different diagnosis, stage, treatment regimen, and set of goals, which is why most nutrition studies involve small groups and rarely provide definitive answers.

There are currently very few published clinical studies specifically evaluating a carnivore diet for cancer patients. That doesn’t mean the diet is harmful or beneficial. It means we don’t have enough evidence to answer the question with confidence. Most published research focuses on ketogenic diets, which share similarities with carnivore but are not identical. Whenever someone claims science has already proven carnivore cures cancer, I become skeptical. I haven’t seen evidence supporting that claim.

I chose this path anyway because I wasn’t betting on one study. Stable blood sugar, preserved muscle, adequate protein, fewer processed foods, regular exercise, a healthy weight, these are worthwhile regardless of whether they directly affect tumors. Even if future research shows carnivore has little direct effect on cancer, I still believe improving my overall health was the right call.

Nothing here should be read as encouragement to refuse conventional treatment. If I had rejected surgery, radiation, or immunotherapy, I likely wouldn’t be writing this. My decision was never conventional medicine versus metabolic health. It was conventional medicine plus metabolic health.

Conclusion: Why I Chose This Path

I often think back to sitting in my car in June 2025, hearing that the cancer had spread to my lungs. I made the hardest decision of my treatment there: move forward with Keytruda, decline more chemotherapy, and commit to giving my body every reasonable advantage alongside it.

Would I make the same choice today? Absolutely. Not because I believe I found a miracle, but because it let me become an active participant in my own care instead of a passenger.

Hope is not a treatment plan. But neither is hopelessness. Hope should inspire action, action should be guided by evidence, and evidence should be weighed with humility, because there is still so much we don’t know about cancer.

If you’ve recently been diagnosed, my encouragement is simple. Become an informed patient. Ask questions. Read reputable research. Work closely with your medical team. Take care of your body, your mind, and your spirit. Statistics describe groups. They do not determine individual outcomes.

Today I get another sunrise. Another chance to encourage someone else. Another chance to thank God for the gift of another day.

That is enough.

With faith and gratitude,

Wayne Schlicht

WaynesCancerJourney.com

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Frequently Asked Questions for my Metabolic Theory of Cancer Journey