Part 2 of our Rain Barrel series. Start with Part 1: What If Your Genes Aren’t Your Destiny?
Ask most people what causes cancer and you’ll hear one word: genes. That answer isn’t wrong. Genetic mutations are a central, well-documented part of how cancer develops. But it’s incomplete — and over the last decade, one of the biggest shifts in cancer biology has been the growing recognition that how a cell produces and uses energy is just as fundamental to understanding the disease.
So is cancer a metabolic disease? The honest answer is more interesting than a yes or no. Here’s what the research actually shows, where the debate stands, and why it matters for anyone thinking about prevention.
Where the Idea Started: The Warburg Effect
In the 1920s, German biochemist Otto Warburg noticed something strange. Many tumor cells were consuming glucose at very high rates and breaking it down through glycolysis — a fast, less efficient pathway — even when there was plenty of oxygen available for the more efficient mitochondrial route. Healthy cells usually reserve that pattern for low-oxygen situations.
This became known as the Warburg effect, and it’s why PET scans can find many tumors: patients receive a radioactive glucose tracer, and glucose-hungry cancer cells light up. Warburg believed damaged cellular respiration was the origin of cancer. For decades that view was overshadowed as genetics took center stage — but his observation never went away.
Why Would a Cancer Cell Choose the “Inefficient” Path?
Glycolysis yields far less ATP per glucose molecule than mitochondrial respiration. So why would rapidly growing cells use it? Researchers now think the answer is that cancer cells need more than energy. They need raw materials — building blocks for new membranes, proteins, and DNA. Running glucose through glycolysis quickly generates intermediates that can be diverted into those building blocks. Cancer cells also rewire their use of amino acids like glutamine, fatty acids, and other nutrients to support survival and growth.
The Metabolic Theory of Cancer: Thomas Seyfried’s Argument
Boston College professor Thomas Seyfried, author of Cancer as a Metabolic Disease, has taken Warburg’s idea further. He argues that damage to mitochondria — and the cell’s resulting shift to fermentation-based energy — is the origin of cancer, with many genetic mutations arising downstream of that metabolic disruption rather than causing it. His work has fueled research into metabolic approaches such as ketogenic diets alongside standard therapy.
It’s important to be clear: this metabolic-origin hypothesis remains debated. Most cancer researchers still view genetic and epigenetic changes as primary drivers, and many tumors don’t fit a single metabolic pattern. Metabolic or dietary strategies are not substitutes for established cancer treatment and should only be explored with your oncology team.
What Mainstream Cancer Science Now Agrees On
Even without settling the origin debate, mainstream cancer biology has moved decisively toward metabolism. In 2011, Douglas Hanahan and Robert Weinberg added “deregulating cellular energetics” as an emerging hallmark of cancer. In Hanahan’s 2022 update in Cancer Discovery, reprogramming cellular metabolism was promoted to a core hallmark — meaning a decade of research had validated it as a defining capability of cancer cells.
That same update named nonmutational epigenetic reprogramming as an enabling characteristic — changes in gene expression that don’t involve DNA mutations at all. And research increasingly shows metabolism and epigenetics talk to each other: metabolites like acetyl-CoA, S-adenosylmethionine, and alpha-ketoglutarate are the very molecules enzymes use to place and remove epigenetic marks. The emerging picture isn’t genes versus metabolism. It’s genes, metabolism, epigenetics, immunity, and the tumor environment working together.
The Metabolic Health Connection You Can Act On
Here’s where this research becomes personal. Whatever the exact origin of cancer, the metabolic environment of the whole body clearly influences risk:
- Excess body weight was responsible for an estimated 7.6% of U.S. cancer cases in 2019 — second only to smoking — according to a 2024 American Cancer Society analysis.
- Insulin resistance and high insulin levels are associated with higher risk of several cancers, including colorectal, liver, pancreatic, and endometrial cancer. Insulin and the related growth factor IGF-1 are growth-promoting signals.
- Type 2 diabetes is linked to elevated risk of several cancer types, and chronic low-grade inflammation — common in metabolic syndrome — creates a more permissive environment for tumor growth.
- Physical inactivity accounted for an estimated 3.1% of cancer cases in the same ACS analysis.
And metabolic dysfunction is extremely common. A study of national NHANES data published in Metabolic Syndrome and Related Disorders found that only about 12% of American adults met optimal levels for blood sugar, blood pressure, triglycerides, HDL cholesterol, and waist circumference without medication. That means most of us are carrying some metabolic water in our rain barrel.
What This Does — and Doesn’t — Mean
It does mean improving insulin sensitivity, building muscle, moving daily, sleeping well, and eating whole foods are meaningful cancer-prevention behaviors, not just weight-loss tips. It does mean metabolic markers like fasting insulin, glucose, HbA1c, and triglycerides deserve attention long before a diagnosis of type 2 diabetes.
It doesn’t mean sugar “feeds cancer” in a simple way that can be fixed by cutting carbs, or that any diet, supplement, or IV therapy can cure cancer. Every cell in your body uses glucose. The point isn’t fear of food — it’s long-term metabolic health.
How Core iV Therapy Supports Metabolic Health
At Core iV Therapy in Herndon, VA, our approach is to bring the body’s baseline up: hydration, nutrients, open detox pathways, oxygen, and metabolic and mitochondrial support. For clients focused on metabolic health, that can include our insulin resistance program, medical weight loss, the ProLon Fasting Mimicking Diet, NAD+, and our Mitochondrial Optimization drip.
For people already in cancer treatment, our Cancer Care Support services — including high-dose vitamin C when appropriate — are designed to complement your oncologist’s plan, never to replace it, and are coordinated with your medical team.
Frequently Asked Questions
Is cancer a metabolic disease?
Altered metabolism is now recognized as a core hallmark of cancer in the 2022 Hallmarks of Cancer framework. The stronger claim that cancer originates primarily as a mitochondrial or metabolic disease, advanced by Thomas Seyfried, is still debated. Most researchers see cancer as involving genetic, epigenetic, metabolic, and immune changes together.
What is the Warburg effect?
The Warburg effect, first described by Otto Warburg in the 1920s, is the tendency of many cancer cells to break down glucose through glycolysis at high rates even when oxygen is available. It helps fast-growing cells generate building blocks for new cells and is the basis for glucose-tracer PET scans.
Does sugar feed cancer?
All cells, healthy or not, use glucose, and cutting sugar will not starve a tumor. However, chronically high blood sugar and insulin, insulin resistance, and excess body weight are linked to higher risk of several cancers, so long-term metabolic health matters.
How does insulin resistance relate to cancer risk?
Insulin resistance leads to higher circulating insulin and related growth signals like IGF-1, plus chronic inflammation. These are associated with increased risk of cancers including colorectal, liver, pancreatic, and endometrial cancer.
Can Core iV Therapy treat cancer?
No. Core iV Therapy in Herndon, VA offers supportive wellness services that are meant to complement, not replace, care from your oncologist. Any support during cancer treatment should be coordinated with your medical team.
Start With Your Metabolic Baseline
Want to know where your metabolic health stands? Call Core iV Therapy at 866-426-7348, stop by 108 Elden Street, Suite 15A, Herndon, VA 20170, or request a free phone consultation to talk about functional wellness testing and a plan that fits your goals.
Research and References
- Warburg O. On the origin of cancer cells. Science. 1956;123:309–314.
- Seyfried TN, et al. Cancer as a metabolic disease: implications for novel therapeutics. Carcinogenesis. 2014;35:515–527.
- Hanahan D, Weinberg RA. Hallmarks of cancer: the next generation. Cell. 2011;144:646–674.
- Hanahan D. Hallmarks of Cancer: New Dimensions. Cancer Discovery. 2022;12:31–46. PubMed.
- Islami F, et al. Cancer cases and deaths attributable to potentially modifiable risk factors in the United States, 2019. CA Cancer J Clin. 2024. PubMed.
- Araújo J, Cai J, Stevens J. Prevalence of optimal metabolic health in American adults: NHANES 2009–2016. Metab Syndr Relat Disord. 2019;17:46–52.
This article is for educational purposes only and is not intended to diagnose or treat any disease. Cancer requires evaluation and treatment by qualified medical professionals.