Brussels Sprouts, Broccoli and Cabbage

I recommend cruciferous vegetables for dogs with cancer. Why? Many reasons. Broccoli, Brussels sprouts, and cabbage have some direct anti-cancer benefits ... and they offer excellent liver support in general. The liver is overworked in cancer, particularly if you are using chemotherapy. Learn how these vegetables help your dog.

A photo of Brussels sprouts broccoli and cabbage

Read Time: 4 minutes

The diet in my book The Dog Cancer Survival Guide is designed specifically for dogs with cancer.  When you read it, you might think some ingredients are kind of strange and wonder whether maybe Dr. Dressler has lost a few marbles along the way.  Brussels sprouts, broccoli, and cabbage for dogs?  Seems pretty unnatural … right?

Right you are.  Dogs in nature do not necessarily eat these strange plants.

But dogs with cancer need extra help. They are out of balance, so we need to correct the balance when we feed them. If we only fed their “natural diet,” it would not be enough.

So why do I recommend Brussels sprouts, broccoli, and cabbage?

These veggies are superheroes in detoxifying the body and helping fight cancer.

Brussels Sprouts Broccoli and Cabbage in Dog Cancer Diet: Why Use Them

These three veggies were chosen for several reasons. Each has demonstrated health benefits for cancer and detox support, among many other benefits.1

The nice thing about detoxification support for dogs with cancer is that they ALL can use it. Whether they are going through chemotherapy, radiation, or are just on regular prescription drugs, they need extra detox support. Cancer itself is also creating waste products that need to be removed from the body pronto. And what detoxes the body?

The liver. So let’s look at liver detox.

I’m not talking about some vague idea of “detox,” “cleanse,” or “purify the body.” A liver detox is not a spiritual event, it’s a (hopefully) daily occurrence that is critical to health.

A liver detox is not a spiritual event, it’s a (hopefully) daily occurrence that is critical to health.

Let’s look at some science for a moment, so we can appreciate exactly what happens in the liver.

What Exactly is a Toxin?

So what are we talking about when we say “detoxification?” Of course, we are getting rid of toxins.

What are toxins? Anything that hurts the body is a toxin. Some toxins come from outside the body, like insecticides or air pollution, and there are LOTS of toxins that are produced inside the body during normal body processes.

Here are just a few toxins that build up in a normal body minute by minute:

  • Normal cells produce metabolic waste just by doing their normal jobs.
  • Micro-organisms.
  • Contaminants and pollution are absorbed through the skin, food, air, and water.
  • Insecticides and pesticides.
  • Food additives, drugs, or alcohol.

The body, in its infinite wisdom, puts all of these toxins in the liver to detox them away. How? We’ll go over that below.

Now, most dogs don’t drink or do drugs. But what about the drugs we give them as medicines? Oh, yeah, those can be toxins, too, if left in the body. A variety of toxic chemicals can be left by the drugs themselves or created when they break down. Most dogs do fine on chemo and radiation, with little obvious reaction. Still, rarely, these toxins can promote later cancer growth.

Those toxins also end up in the liver to be detoxed away.

But even if a dog isn’t on chemo or radiation, there are a bunch of toxins that every dog with cancer deals with:

  • Cancer gobbles up starch (sugar) and creates a toxin called lactate.
  • Cancer releases acid, which is toxic.
  • Cancer creates inflammation, which results in lots of damaging free radicals.

These toxins also end up in the liver, and if they aren’t detoxed, they can lead to cancer growth later.

How to Support the Liver without Interfering with Cancer Treatments

So how do we support the liver’s natural detox practices without interfering with cancer treatments? There are many different ways to do this, but a simple one you can do at home is with your dog’s diet. And this is where the Brassica plants like Brussels sprouts, broccoli, and cabbage come in!

The Three Phases of Liver Detoxification

Liver Detoxification has 3 Phases, all designed to convert fat-soluble toxins into water-soluble toxins.2

Why do we want water-soluble toxins? Because fat-soluble toxins will stay in the body forever, essentially. They nestle up in fatty little deposits (either in the liver or in other fat stores).

On the other hand, water-soluble toxins wash out of the body in urine and bile.

So … one of the liver’s main jobs is to take fat-soluble toxins and change them into water-soluble versions.

The liver’s main jobs is to take fat-soluble toxins and change them into water-soluble versions.

Phase 1 Liver Detox

Phase 1 uses nutrients from food to start the change from fat-soluble to water-soluble. There are lots of nutrients needed (one reason why diet is so important for all of us). It’s nice that Brussels sprouts, cabbage, and broccoli all contain good amounts of many of these nutrients.

Weirdly, sometimes the things that happen in Phase 1 increase the toxicity of the substance.  Oops!

Phase 2 Liver Detox

Thankfully, the Phase 2 systems catch the bulk of these and inactivate them using special chemical groups.  And guess which veggies crank up the Phase 2 systems?  You guessed it: Brussels sprouts, broccoli and cabbage!3 (Also, garlic which is another “helpful food” in my dog cancer diet!)

Phase 2 in the liver adds these chemical groups to increase water solubility.

Phase 3 Liver Detox

Once everything is nice and watery, Phase 3 involves shipping the now-water-soluble toxin to organs of elimination. This rids it from the body!

Most of the water-soluble toxins exit via the kidneys in urine. But the rest exits the liver and goes into the gall bladder, where the bile, another bodily fluid, carries them out into the intestines to exit via bowel movements.

Turns out these veggies help out with Phase 3 detox too.  They add bulky fiber (without adding sugar).  This stimulates more release of bile into the intestine. Freely flowing bile is a big part of clearing toxins in Phase 3.

Brussels sprouts, broccoli, and cabbage all provide lovely anti-cancer support AND can be used in all three phases of liver detox.

And that’s why I include these powerhouse veggies in the dog cancer diet!


Dr D

Editorial Note: This post was originally published on a retired blog about dog cancer.

1. Mateljan G. The World’s Healthiest Foods: Optimize Your Health with Health-Promoting Superfoods and Nutrient-Rich Cooking. Seattle, WA: George Mateljan Foundation; 2015.

2. Susa ST, Preuss CV. Drug metabolism – statpearls – NCBI bookshelf. Drug Metabolism. Published September 21, 2022. Accessed December 11, 2022.

3. Munday R, Munday CM. Induction of phase II detoxification enzymes in rats by plant-derived isothiocyanates: Comparison of allyl isothiocyanate with sulforaphane and related compounds. Journal of agricultural and food chemistry. Published April 7, 2004. Accessed December 10, 2022.

Dr. Demian Dressler, author of The Dog Cancer Survival Guide

Demian Dressler, DVM

Dr. Demian Dressler is the owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog's Life Quality and Longevity.



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