Understanding Cancer & Metabolism
- Randa Foda MD
- 2 days ago
- 10 min read
BeeWell™ Wellness Practice
Patient Education Series
Understanding Cancer & Metabolism:
What Your Body’s Energy System Has to Do With Your Cancer
Written by Randa Foda, MD, ABFM, ABOM
Board-Certified Family Medicine & Obesity Medicine Physician | BeeWell™ Wellness Practice
Who This Article Is For This guide is written for cancer patients, survivors, and their families who want to understand how metabolism affects cancer — and what certain medications and lifestyle changes can do to help. No medical background is needed. Plain language, real science. |
🧠 Part 1: Cancer and Energy — The Connection Most People Don’t Know About
So What Actually Causes Cancer?
Most people have heard that cancer is caused by “mutations” — mistakes in the DNA of cells. That’s true, and it’s part of the story. But there’s another piece of the puzzle that scientists are increasingly excited about: the way cancer cells use energy.
Normal cells in your body are like efficient hybrid cars. They use oxygen and burn fuel cleanly, getting the most energy out of every glucose molecule. Cancer cells are more like an old car with a broken engine — they burn fuel inefficiently, use far more of it, and make a mess of byproducts in the process.
The Warburg Effect: Cancer’s Unusual Appetite
Back in the 1920s, a German scientist named Otto Warburg noticed something strange: cancer cells preferred to ferment glucose (sugar) into lactic acid, even when there was plenty of oxygen available. Normal cells only do this when oxygen is scarce. Cancer cells do it all the time.
This is called the Warburg Effect, and it has become one of the most important discoveries in cancer science. Here’s what it means in plain terms:
Cancer cells are addicted to sugar (glucose).
They consume glucose at a rate 10 to 40 times higher than normal cells.
They also rely heavily on glutamine — an amino acid that comes largely from muscle protein.
This constant demand for fuel is what drives tumor growth, spread, and survival.
Why Does This Matter for You? If cancer cells need large amounts of glucose and glutamine to survive and grow, then anything that reduces the availability of those fuels — or disrupts how cancer cells use them — can slow down or stop tumor growth. This is the foundation of metabolic oncology. |
The Role of Mitochondria
Mitochondria are the power plants inside your cells. In cancer cells, these power plants are broken or abnormal. Scientists now believe this breakdown may actually come first — before the DNA mutations we associate with cancer. When the mitochondria malfunction, the cell switches to the sugar-burning mode that Warburg described, and this sets off a cascade that eventually leads to tumor formation.
This doesn’t mean DNA mutations aren’t important — they are. But it does mean that treating the metabolic dysfunction may be just as important as targeting the genetic changes.
💊 Part 2: Metformin — A Diabetes Drug That Fights Cancer?
What Is Metformin?
Metformin is a medication most people know as a diabetes drug. It lowers blood sugar and has been safely used for decades in millions of patients worldwide. But researchers noticed something interesting: diabetic patients taking metformin had significantly lower cancer rates than those on other diabetes medications.
That observation sparked decades of research, and today the evidence is compelling: metformin has real, measurable anti-cancer effects.
How Metformin Works Against Cancer
Metformin’s anti-cancer effects work through several pathways. You don’t need to memorize these, but understanding them in broad strokes helps explain why this drug is so promising:
Metformin’s Anti-Cancer Mechanisms (Plain Language)
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What Does the Research Show?
Large studies have found that people with diabetes who take metformin are 30 to 50% less likely to develop certain cancers compared to those on other medications. This includes liver, colorectal, pancreatic, breast, and prostate cancers. Clinical trials in non-diabetic cancer patients are now ongoing.
Important Note Metformin is not yet FDA-approved as a cancer treatment. However, many oncologists and integrative medicine physicians are increasingly considering it as an adjunct therapy, especially for patients who also have diabetes, prediabetes, or insulin resistance. Talk to your doctor about whether it might be appropriate for you. |
💉 Part 3: GLP-1 Medications (Like Ozempic & Mounjaro) and Cancer
What Are GLP-1 Medications?
GLP-1 receptor agonists are a class of medications you’ve likely heard about under brand names like Ozempic® (semaglutide), Wegovy®, Victoza®, and Trulicity®. They were originally developed for type 2 diabetes and are now widely used for weight loss. They work by mimicking a natural hormone your gut releases after eating, which triggers insulin release, reduces appetite, and slows digestion.
Tirzepatide (Mounjaro®, Zepbound®) is the newest class — it targets two receptors simultaneously (GLP-1 and GIP), making it even more powerful for weight loss and metabolic health.
Do These Drugs Affect Cancer Risk?
The research here is exciting and still evolving. Here’s what we know:
What Major Studies Show About GLP-1 Drugs and Cancer
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Why Might These Drugs Protect Against Cancer?
Several reasons, working together:
Weight loss: Obesity is linked to at least 13 types of cancer. By helping people lose weight, GLP-1 drugs reduce a major cancer risk factor.
Lower insulin and blood sugar: Less fuel available for cancer cells to consume.
Immune system benefits: These drugs may help the immune system recognize and attack cancer cells.
Direct anti-tumor effects: Especially with tirzepatide, research shows the drug can directly disrupt the cancer cell’s ability to burn glucose — essentially starving it.
Tirzepatide: A New Frontier A landmark 2025 study showed that tirzepatide (Mounjaro/Zepbound) can directly block cancer cells’ ability to use glucose, targeting a key protein (HIF-1α) that cancer needs to run its energy machinery. It also worked synergistically with chemotherapy drugs in lab models. This research is early but very promising. |
⚠️ Part 4: The Hidden Problem With Steroids in Cancer Treatment
This section covers something that many cancer patients are never told — and it’s important enough to discuss openly with your care team.
Why Steroids Are Used in Cancer Treatment
Steroids (like dexamethasone, prednisone, or methylprednisolone) are given to cancer patients for many legitimate and important reasons:
To prevent nausea and vomiting from chemotherapy
To reduce brain swelling from tumors
To treat allergic reactions to medications
To manage immune-related side effects from immunotherapy
To reduce inflammation and improve energy or appetite
These are real benefits, and in many situations steroids are absolutely the right choice. But there is a significant metabolic downside that is often overlooked.
The Problem: Steroids Spike Blood Sugar
All steroids raise blood sugar — significantly. Dexamethasone is particularly potent in this regard. In fact, 10 to 30% of cancer patients experience episodes of high blood sugar (hyperglycemia) during steroid treatment, and some develop steroid-induced diabetes.
Remember what we learned earlier: cancer cells are addicted to sugar. When steroids flood the bloodstream with glucose, they are essentially delivering more fuel directly to the tumor. This is the paradox: a drug meant to help you may inadvertently feed your cancer.
The Steroid Paradox Steroids reduce inflammation and manage side effects — but they also spike blood sugar (feeding cancer cells), break down muscle (raising glutamine, the second cancer fuel), suppress your immune system (reducing your body’s ability to fight the tumor), and may reduce the effectiveness of immunotherapy drugs. |
What the Research Shows About Steroids and Immunotherapy
If you are receiving immunotherapy (like checkpoint inhibitors — drugs such as pembrolizumab/Keytruda® or nivolumab/Opdivo®), the steroid concern becomes even more urgent.
A large study of over 2,000 immunotherapy patients found that those who were on steroids at the start of treatment had a 23 to 47% higher risk of death compared to those who were not. A 2024 analysis of six major clinical trials found that patients who received high-dose steroids had significantly worse survival outcomes.
This doesn’t mean you should refuse steroids. It means the dose and duration should be as low as possible, and your team should have a plan to minimize steroid exposure whenever it is safe to do so.
Steroid Risk by Use: What to Discuss With Your Doctor
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What You Can Do
You don’t have to simply accept all the risks. Here are constructive conversations to have with your care team:
Ask: “Can I use the lowest effective steroid dose?” New guidelines confirm a single dose of dexamethasone before chemo is often as effective as a 3-day course.
Ask: “Is there a steroid-sparing anti-nausea option for me?” Other antiemetics may work without the blood sugar spike.
Ask: “Should my blood sugar be monitored during steroid treatment?” Especially if you already have diabetes, prediabetes, or are overweight.
Ask: “Could metformin or a GLP-1 medication help counteract the blood sugar spike from steroids?” In some patients, this may be an option worth considering.
🌿 Part 5: Natural Compounds That Support Metabolic Health in Cancer
Beyond prescription medications, a growing body of research supports the role of certain natural compounds in targeting cancer metabolism. These are not cures or replacements for conventional treatment — but they may offer meaningful complementary support when selected carefully and used under medical supervision.
Compound | What It Does for Cancer Metabolism | Key Foods / Source |
Berberine | Works similarly to metformin — activates AMPK, blocks cancer growth signaling, reduces glucose uptake by tumor cells | Supplement (berberine HCl); found in goldenseal, barberry |
Curcumin(Meriva® form) | Blocks key cancer survival proteins (NF-κB, HIF-1α); also reduces inflammation without suppressing immunity like steroids do | Turmeric; enhanced absorption via Meriva® supplement |
EGCG(Green Tea Extract) | Blocks cancer cells’ ability to absorb glucose; activates AMPK; reduces cancer stem cell activity | Green tea; concentrated supplement |
Quercetin | Inhibits cancer growth signaling (PI3K/mTOR); reduces cancer blood vessel formation; sensitizes tumors to chemo | Onions, apples, capers; supplement |
Resveratrol | Activates tumor suppressor genes; inhibits cancer growth via SIRT1 and mTOR; promotes cancer cell death | Red grapes, dark berries; supplement |
Vitamin D3 | Anti-proliferative and pro-apoptotic in many cancers; often depleted by steroid use | Sun exposure; fatty fish; D3 supplement |
Important Reminder Not all supplements are safe during cancer treatment. Some can interfere with chemotherapy or immunotherapy. Always review any supplement with your oncologist or integrative medicine physician before starting. The compounds listed above have been selected based on evidence and safety profiles, but individual circumstances vary. |
🍽️ Part 6: What You Can Do Starting Today
You are not a passive bystander in your cancer care. The metabolic framework gives you concrete, evidence-backed actions to take alongside your conventional treatment. Here are the most important starting points:
Practical Steps to Support Metabolic Health During Cancer Treatment
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💛 A Note From Dr. Foda
The science of cancer metabolism is one of the most exciting and rapidly advancing areas in oncology today. For many years, the conversation in oncology focused almost exclusively on genetics — finding the right mutation to target with the right drug. That work has been transformative and has saved many lives.
But the metabolic view of cancer opens up a whole new set of tools: medications we already have (metformin, GLP-1 drugs), dietary strategies, targeted nutraceuticals, and an urgent reexamination of some common practices (like high-dose steroid use) that may be inadvertently working against us.
At BeeWell™, our mission is to bring this science to patients in language they can understand and act on. You deserve to know not just what medications you are taking, but why — and what your body’s metabolism has to do with your cancer journey.
Please bring this document to your next appointment and use it as a starting point for conversation with your oncology team. You are your own best advocate.
With care,
Dr. Randa Foda, MD, ABOM
BeeWell™ Wellness Practice | Mount Laurel, NJ
This educational article is intended for informational purposes only and does not constitute medical advice. The information herein is based on current scientific literature and the author’s clinical expertise. Individual treatment decisions should always be made in consultation with your oncology care team. © 2026 BeeWell™ Wellness Practice.
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