Is the Ketogenic Diet Best for Dogs with Cancer

🧠 The Science Behind Keto, Fasting, and Cancer — and Why It Matters for Dogs

🐶 What a Navy SEAL Experiment Taught Us About Cancer

Sometimes, breakthroughs in human medicine start in unexpected places — even underwater.

🎥 A team of researchers studying divers discovered something remarkable.

While testing how to prevent oxygen-induced seizures in divers, they found that the ketogenic diet could protect the brain from overstimulation.

When the brain was under high oxygen pressure, neurons became overstimulated and burned through energy too fast — a setup for seizures. But when fueled by ketones instead of glucose, the brain became more stable and resilient.

👉 The result: fewer seizures, better brain energy, and a protective effect against damage.

This discovery led to an even bigger question — if ketones protect healthy cells from stress, could they also protect against diseases like cancer? And, more importantly for us, can this be applied to our dogs?

I can tell you that both the research, and my personal experience over the lat 25+ years working with dogs, especially seniors and dogs with cancer or autoimmune disorders, that the keto diet will help… if you know how to use it…

Note: part of this article uses info presented in the Ted Talk given by Doctor Dominic, superstar cancer doctor and researcher. You can watch the video below:

🧬 What Is the Ketogenic Diet?

At its core, the ketogenic diet is simple:

🥩 Very low in carbohydrates (as close to zero as possible)

🧈 High in healthy fats

🍗 Low to Moderate in protein

This forces the body to shift from burning glucose (sugar) to burning fat — producing ketones as a clean, alternative fuel.

And here’s the key point:

✅ Healthy cells can use ketones.

❌ Cancer cells cannot.

Don’t let the “low in protein” aspect scare you. No one is more serious about adult and senior dogs getting enough protein that I. Seniors especially need to guard their lean muscle like their life depends on it… because it does.

While the keto diet is lower in protein than normal, keep in mind that fats are protein sparing. Their bodies will draw on fats for energy, and spare the protein. This is different than carb-heavy diets that can cause the body to use protein as an energy source.

Plus, our keto diets are rich in highly bioavailable protein, meaning your dog will utilize most of what they eat for repair and rebuilding.

🔬 Why Cancer Cells Struggle With Ketones

Dr. Otto Warburg first observed this over 80 years ago — cancer cells have a damaged metabolism. They crave glucose and can’t adapt to burning ketones for fuel.

That “sugar addiction” is their Achilles heel.

Modern researchers like Dr. Thomas Seyfried and Dr. Dominic D’Agostino have confirmed this: cancer is fundamentally a metabolic disease.

Cancer cells:

🍬 Depend heavily on glucose (sugar)

💥 Thrive in low-oxygen environments (where healthy cells slow down)

🚫 Can’t switch to ketones when glucose runs out

Healthy cells, on the other hand, are metabolic hybrids — they can thrive on both glucose and ketones.

🤓 Nerd Alert!

The Warburg Effect (1931)

Dr. Otto Warburg, Nobel laureate in physiology, first observed that cancer cells depend heavily on glucose for energy and thrive in low-oxygen environments.

His discovery became known as the Warburg Effect, the foundation of today’s metabolic therapy approach.

Hamburg, O. (1931). The Metabolism of Tumours. London: Constable Press.

⚡ Cancer as a Metabolic Disease

Modern researchers like Dr. Thomas Seyfried (Boston College) expanded on Warburg’s work, showing that cancer cells have damaged mitochondria and cannot effectively use ketones for fuel.

By reducing glucose and raising ketones, we can selectively stress cancer cells while feeding healthy ones.

Seyfried, T. N. (2012). Cancer as a Metabolic Disease: On the Origin, Management, and Prevention of Cancer. Wiley Press.

🐕 How This Applies to Dogs With Cancer

Dogs’ metabolisms work similarly to ours when it comes to energy sources.

When you feed your dog a high-carb, kibble-based diet, you’re essentially feeding those potential cancer cells their favourite fuel — glucose. Let’s be honest here, even grain free food is usually loaded with carbs.

And no, the expensive dog food is not immune. Nor is “vet approved” foods. They are some of the biggest offenders, along with senior dog foods.

By contrast, switching to a ketogenic or low-carb homemade diet:

🛡️ Starves cancer cells of glucose

⚡ Provides clean energy for healthy cells via ketones

💪 Reduces inflammation and oxidative stress

🧬 Supports mitochondrial health (the cell’s “engine room”)

And when paired with intermittent fasting, you further enhance autophagy — the body’s natural cleanup system that destroys damaged cells and supports regeneration.

For dogs, intermittent fasting is not about starvation, or letting dogs go without food for long periods. It is simply an organized method of restricting foods for short periods of time.

🍗 This means, essentially, if your dog eats at 8am and then again at 5pm, and they eat no treats after dinner, you are creating a 13 hour fasting window.

The’ll be asleep for most of that block of time. There isn’t much data on dogs, but it seems about 12 hours is fine for encouraging autophagy, especially when combined with a keto diet.

This can help blunt excess, low grade inflammation, plus help your dog get into, and stay in, ketosis.

🦮 Ghangis’ Story - The Keto Diet in Real Life for a Dog with Stage 3 Cancer

All the studies are great, and so is the science talk, but what does this look like in real life?

This is where a lot of sites go wrong. They present a perfect plan… that only works under perfect conditions. I’ve had years of experience using the keto diet for seniors for general health, autoimmune disorders, and cancer.

Let’s dive into a tough case. Tough because the dog in question had a head like granite when it came to doing things she didn’t want to do, like take medicine, eat something that wasn’t to her liking in that EXACT MOMENT, etc.

Ghangis was 13 when she was diagnosed with cancer. It snuck up on us. Just 2-months earlier, she had a clean blood panel. This was a complete exam, not just an emochromo, so this should let you know how sneaky cancer can be.

In fact, it was only discovered when a tumour appeared under her tail, and it grew rapidly.

She needed MRIs to find the issue, which was a cancer that was in her lymph nodes and lymphatic system, which is a particularly nasty cancer.

Unfortunately, her first oncologist was completely uninterested in helping her. She arrived at the clinic with her younger sister, who had just been diagnosed with a genetic autoimmune disorder that required long-term chemotherapy.

By the way, if your adult or senior dog gets cancer, be prepared for this type of treatment. It is, unfortunately, all too common now that so many vets are part of large, corporate clinics. This is why it is always a good idea to get a second opinion.

The oncologist was only interested in Lucia, the younger dog, because she represented long term profits.

An old dog with aggressive cancer? Not much money in that.

Luckily, our regular vet recommended a fantastic oncologist who put Ghangis through EXTENSIVE testing. She found that:

😡 Ghangis was misdiagnosed

🤬 Ghangis was given a basic, barely effective chemo pill that wasn’t going to do much at all

The oncologist gave her a much better medicinal plan, using a chemo-mimicking drug called Palladia, combined with an anti-inflammatory to be used at times.

Now, this is where it gets interesting.

❤️ First, she was the first oncologist or specialized vet who listened to me about pairing the treatment with the ketogenic diet. She admitted that she didn’t know much about it, but it was absolutely worth the try.

🥓 Second, Ghangis was already eating a low carb homemade dog food diet.

We had to wait to get the medicine because it came through the mail (difficult to get at that time in Sicily.

🐕 The change to strict keto caused a dramatic change in appetite and energy. After 2-weeks, she was running and playing and eating like a horse again.

Then the Palladia arrived, and there was a second Great Leap Forward for energy, mood, and appetite.

Now, it is really easy to go supplement crazy in these cases, but it is important to add supplements slowly, and keep track of changes. Sometimes cycling is a good idea, other times, staying on supplements long term is best.

✅ If you need help, Click Here to download our free supplement guide for dogs.

This is what her supplement regime looked like. You’ll notice a lot of the “supplements” are real food based.

🏵️ Homemade Turmeric Paste - this negated the need for the anti-inflammatory, so it was only used if she pushed her self too hard running around like a maniac.

🍶 Kefir - This is used to promote optimal GUT health. This is only recently being talked about for dogs. Adult and senior dogs need great GUT health. This is true if they are disease-free, if they have liver problems, CKD, Cancer, etc.

The path to living longer starts in the GUT. Our kefir is homemade, but the stuff from the store is perfectly fine, I’m just a kefir nerd.

🐠 High EPA/DHA Omega 3s - The second step in both cancer survival, and longevity, is with omega 3s. High EPA + DHA oils are absolutely fantastic for adult and senior dogs, especially if they are battling serous health problems.

ApoCaps: A super effective blend of “adapotgen” supplements formulated specifically for dogs with cancer by Dr. Damien Dressler, author of the Dog Cancer Survival Guide (a must-read. Click here for our review)

Turkey Tail Mushrooms - used in cycles. These have been shown to help the body fight tumour growth.

Homemade Bone Broth - another food used as a supplement. Broth is great not only for collage, but also for GUT health improvement, as well as helping your dog produce new, better STEM cells.

🤔 But what did her diet actually look like?

Was her keto plan filled with exotic, expensive foods?

Of course not. Homemade meals should be simple and loaded with the right nutrients:

The Result?

Despite first getting a prediction of, “eh, maybe a month or two,” Ghangis THRIVED for nearly 19-months.

Now, I don’t mean she limped around, sad, lethargic, and barely eating. I mean she THRIVED.

Walked 45-minutes a day. Played with her tennis balls for, well, as long as it took for her to destroy them. She ate like a queen.

Her health broke down in her final day and a half.

Not a bad deal for a 14+ year old big dog with cancer.

She was a warrior. I miss her every minute of every day, and I hope her journey continues to help other dogs with cancer live longer and thrive.

🌊 The Hyperbaric Connection

Here’s where the keto diet for dogs with cancer research gets even more fascinating.

In lab studies, when researchers combined the ketogenic diet with hyperbaric oxygen, cancer cells were destroyed — while healthy cells remained unharmed.

💨 Cancer cells overproduced free radicals and self-destructed under high oxygen.

🧘 Healthy cells thrived in that same environment.

This synergy — ketosis + oxygen therapy — shows how diet can change the internal “terrain” of the body to make it harder for cancer to survive.

For dogs, regular hyperbaric oxygen treatments are still new and often expensive — but we can mimic parts of the same effect through:

🥦 Antioxidant-rich veggies (for balanced oxidative stress)

🥩 Ketogenic homemade meals (for metabolic stability)

⏳ Gentle fasting (for mitochondrial cleanup and repair)

The Keto Pet Sanctuary has been using the keto diet, combined with traditional and non-traditional therapies to treat dogs with cancer for the last few decades.

If you want to go into a deep dive into how and why keto combines well with various therapies like chemo, oxygen, radiation, etc., definitely check out their site.

🐾 Practical Tips for Dog Parents

You can apply this science safely at home — here’s how to start:

💧 Hydration is everything.

Dehydration can slow ketosis and stress the liver and kidneys. Hydration is also a necessity to avoid the “keto flu” that can affect some dogs (and humans). Hydration, using bone broth and wet, real food, is an easy, fast fix.

🥩 Feed real food.

Use grass-fed meats (if this is in your budget) eggs, and healthy fats like coconut oil, extra virgin olive oil, ghee, or tallow. Avoid processed carbs and vegetable oils.

⏳ Incorporate short fasts.

Try the 12-hour window of no-feeding, utilizing the 9 - 10 hours your dog sleeps, toyour dog’s body enter mild ketosis and boost autophagy.

🍳 Use targeted supplements.

MCT oil, turkey tail mushrooms, and omega-3s can support cellular repair.

🧘 Keep stress low.

Stress hormones raise blood glucose — the exact opposite of what you want. This is one of the biggest reasons we recommend reading the Dog Cancer Survival Guide. It deep-dives into how stress, even your stress, can make your dog’s condition worse, and how to manage this so you dog’s system stays happy, stress-free, and strong.

🧀 Choose the best fats:

💡 Key Takeaway

Healthy cells are flexible. Cancer cells are not.

That’s the metabolic truth behind why ketogenic and fasting strategies work — not just for humans, but for dogs too.

As Dr. D says: When we remove sugar, provide clean fats, and let the body rest between meals, we’re returning to the wisdom of Hippocrates:

“Let food be thy medicine.”

❓ FAQ: Keto & Fasting for Dogs With Cancer

Q: Is fasting safe for all dogs?

A: Always monitor energy and hydration. Fasting is NOT a necessity. If your pup is underweight, wait until they’re back to normal weight before trying.

Q: Can I use coconut oil or MCT oil?

A: Yes! Both raise ketones quickly and are easily absorbed, but start slow (½ tsp per 5-kg of bodyweight).

Q: Should I go 100% carb-free?

A: No, not forever. In the beginning, yes, try for as close to zero carbs as possible. After 8 - 12 weeks, start to include small amounts of fiber-rich, low-glycemic vegetables (broccoli, spinach, zucchini) for gut support.

Q: How long does it take for a dog to enter ketosis?

A: This varies widely, from 2-weeks to 3-months. Remember, even in the lead-up to ketosis, your dog’s body is already getting a lot of the benefits, and we’re cutting off the glucose supply to the tumours.

Q: Can this replace chemo or vet treatment?

A: While some people choose to do this, I recommended that the keto diet should complement, not replace, veterinary care. Diet and metabolic support can enhance resilience and recovery. Keto seems to help traditional, and non-traditional therapies work better.

Q: Is the keto diet right for all dogs?

A: No. Dogs with CKD should avoid ketosis. Same for dogs with some liver issues, and pancreatitis. In those cases, low carb is best, but the diet should avoid ketosis.