9 Reasons You Should Fast Your Boxer

We all want to raise Boxers bursting with health and vitality, yet few of us are aware of one of the most powerful ways we can do this: fasting.

By fasting your Boxer as part of his regular dietary routine, you can promote optimal health, prevent disease and often resolve symptoms without medication.

Fasting is a natural part of how dogs have always eaten and its benefits are now supported by an impressive body of scientific evidence.

I am not a vet. This article is intended for general informational and educational purposes. I encourage readers to view my full disclaimer.

1. Fasting Promotes Detoxification

Fasting turbocharges the liver’s detoxification function.

In a fasted state, your Boxer’s body begins to break down fatty tissues.

It’s this process that triggers maximal release of toxins and waste products that are stored in adipose tissue, allowing them to be processed and excreted.

This includes two kinds of toxins:

  1. Stored metabolic waste that the body parked in fat because it was too overburdened to process it at the time
  2. Toxins ingested, absorbed or inhaled

Toxins accumulate in the body over years from a multitude of sources including but not limited to:

  • Household cleaning products
  • Pesticides and herbicides sprayed on grass then inhaled or licked off feet
  • Chemicals left as residues in the fatty tissues of livestock then eaten in meat
  • Contaminants in tap water
  • Flea and tick insecticides
  • Chemical wormers
  • Mycotoxins, antimicrobials and other chemical contaminants in kibble
  • Vaccines injected into the body
  • Medication
  • Exhaust fumes and airborne pollutants
  • Volatile Organic Compounds (VOCs) and off-gasses including flame retardant chemicals used on household goods like appliances, furniture, wall paint and bedding

The elimination of these contaminants lightens the toxic load on the body, reducing the occurrence of health problems including:

2. Fasting Triggers Cellular Repair And Regeneration

Researchers have been able to both:

  • Measure the beneficial effects fasting has on the body
  • Elucidate some of the mechanisms through which fasting achieves those effects

One of these mechanisms is the detoxification that goes on in the liver, as discussed above.

Another related process is what’s known as autophagy (pronounced or-TOFF-uh-gee).

The term autophagy (literally, “eating of self”) was coined by Belgian biochemist Christian de Duve in 1963.

It refers to the way the body breaks down damaged proteins and other cell components in order to create new, healthier ones.

Autophagy happens at a low level in most cell types but is most strongly induced by fasting.

This removal of “toxic assets” is a quality control mechanism central to counteracting the negative consequences of aging.

3. Fasting Resets The Immune System

A team at the University of Southern California led by gerontologist Dr Valter Longo has done a lot of work on fasting and its effects on longevity.

Dr Longo likens autophagy to a sophisticated “self-repair mode”, perfected over 3 billion years of evolution.

This same process, with the same revitalizing effects, goes on in the simplest single-cell organisms and in sophisticated mammals all the way up to and including humans.

Dr Longo suspects autophagy may be capable of restoring almost any damaged system throughout the body.

His researchers have demonstrated that:

  • A prolonged (3-day) fast triggers a “reset” of the immune system, switching on stem cells responsible for regeneration of the blood and immune cells
  • Fasting protects against toxicity in cancer patients receiving chemotherapy if they fast for a 72-hour period prior to receiving the treatment

Dr Longo has used a “fasting-mimicking diet” involving caloric restriction and the avoidance of animal protein in favor of plant-based foods to “trick” the body into thinking it’s fasting.

After following this protocol for five days in a row each month for three consecutive months, the blood of human subjects showed dramatic changes including:

  • Lowered blood glucose (a huge drop in pre-diabetic subjects)
  • Lowered IGF-1, a growth factor linked to ageing and cancer
  • Lowered C-Reactive Protein (CRP), a marker of systemic inflammation which is a risk factor for cardiovascular disease
  • Huge increase in circulating stem cells (this immune system regeneration appears to be triggered by a significant lowering in white blood cell counts during fasting)

4. Dogs’ Guts Function Best With Periods Of Total Emptiness

Dogs are not grazing animals.

They are designed to eat according to natural cycles of boom and bust, abundance and scarcity.

Fasting doesn’t have to mean you feed your Boxer any less food, all up.

You can provide the same number of weekly calories, but distributed in a more natural evolutionary pattern eg. feed every second or third day or feed several days in a row and then fast for a few days.

Note that keeping the gut constantly full of food may temporarily mask the symptoms of acid reflux or gastroesophageal reflux disease (GERD) but digestive rest and fasting is what will heal the gut.

Bilious vomiting or “hunger pukes” are sometimes observed when a dog first transitions from kibble to raw, but these symptoms resolve as proper feeding is continued.

This and other normal symptoms to expect when transitioning to raw feeding are explained in our free How To Raw Feed Your Boxer eCourse, delivered direct to your inbox over seven days.

You don’t want to be feeding your dog many small meals so that he’s effectively eating all day.

5. Fasting Is Part Of A Natural Canine Eating Pattern

Feeding dogs every day, sometimes multiple times per day, is a human preference.

We have trained our dogs to expect food this often, but it’s an eating pattern that is wholly unnatural — and unhealthy — for dogs.

While owners tend to struggle with the idea of withholding food being healthy, daily feeding of your Boxer does him no favors.

Remember, dogs don’t attach emotion to food the way humans do.

Sure, your Boxer may sit in the kitchen at the appointed hour and groan like his throat’s been cut if dinner isn’t forthcoming.

This is habituation, not hunger.

Your dog will quickly adapt and will reap enormous health benefits.  

In natural settings, dogs eat once every two to three days — even less often when prey is unavailable.

As a result of eating this way throughout a million years of evolution, your Boxer’s body is adapted to not only cope with, but thrive, with periods of regular fasting.

According to veterinarian Dr Clare Middle, more than six meals a week may compromise the canine liver’s ability to ever fully detoxify (as discussed in point one), since this only happens when the gut is fully empty.

When a dog is constantly eating, the liver is kept busy dealing with the constant drip-drip of substances absorbed after each meal.

Holistic practitioners understand the danger in this: toxins continue to accumulate without ever being cleared out, until eventually they cross a threshold where disease results.

6. Fasting Can Heal Your Boxer’s Gut

Owners with underweight Boxers often find once they start fasting — particularly after the use of an extended fast of at least 7 days — the dogs gain weight and maintain a healthier body mass thereafter.  

This is because fasting promotes healing of the gut damage that can be responsible for “malabsorption”, where dogs are unable to access the nutrition in the food they eat and don’t put on weight even when fed more food.  

Even in right-weight Boxers, fasting tends to optimize digestion such that dogs require less food to maintain the same weight because their bodies become more efficient at extracting nutrition from what they eat and assimilating it into muscle

Too many Boxers suffer from gastrointestinal problems including:

Fasting is beneficial for all of these conditions.

7. Fasting Can Resolve Your Boxer’s Symptoms

Physicians as far back as Hippocrates, the father of medicine, advocated fasting as a treatment for disease

You will have observed that a dog’s first response to any illness is to stop eating.

Dogs instinctively know that fasting is the quickest way to heal.

As well as being a preventive measure that will boost your dog’s health and avoid disease, fasting is a powerful first response to just about any health issue that comes up.

Fasting frees a dog from the labor-intensive task of digestion, allowing energy to be devoted to healing.

The writings of Herbert Shelton detail the use of fasting to heal both acute and chronic disease in humans.

Veterinarians who understand fasting, such as Dr Richard Pitcairn, advise its use in response to illness, especially if there is a fever.

Dr Pitcairn recommends one to two days fasting — or as long as three to seven days for more chronic or degenerative conditions.

The idea is to fast until there is substantial improvement in symptoms.

In the 1940s and 50s, veterinarian Dr Donald Ogden made extensive use of fasting as a healing modality in both dogs and cats:

“Animals, when sick, will recover, in 99% of the cases through fasting. Fasting is the oldest means of remedy to animals … Every practitioner who will give this meritorious function due concern will realize that ten to 30 days’ abstinence from all food except water is nothing monstrous. I have fasted dogs and cats for periods of time ranging from one to 50 days, depending upon the pathology with excellent results and amazing recoveries being effected”.

He found quiet rest and fasts of three to ten days very beneficial for many inflammatory conditions including:

  • Obesity
  • Underweight conditions
  • Rheumatism
  • Arthritis
  • Constipation
  • Cardiac insufficiency
  • Bronchial disease
  • Allergies
  • Skin disease (9 out of 10 cases improved within two weeks with fasting)
  • Digestive pathologies
  • Ulcers
  • Kidney disease
  • Bladder stones
  • Dental disease including periodontitis
  • Eye disorders
  • Liver pathologies
  • Heartworm
  • Mild lameness
  • Kidney and bladder stones
  • Gastritis (inflammation of stomach lining)
  • Diabetes
  • Liver disorders (unless cirrhosis has developed)
  • Open sores
  • The fever stage of distemper and hepatitis  

Dr Ogden advised against fasting an animal with a wasting disease such as cancer, advanced uremia (high levels of urea in the blood), tuberculosis, prolonged malnutrition, hookworm disease or distemper (except for the fever stage).

8. Fasting Balances Fat Overconsumption

Fasting is not about weight loss, though it can be used to achieve caloric restriction if your dog is overweight or obese— a description that fits more than half of the American pet dog population.

Fasting is about getting the body into a metabolic state where its detoxification processes — particularly those that go on in the liver — function most optimally and where autophagy is triggered.

Nevertheless, a quick word about obesity in Boxer dogs.

We are so accustomed to seeing overweight dogs that owners often think an ideal-weight dog is too skinny.

A Boxer’s right weight is less about what the scales say and more about how the dog looks, his energy levels and his behavior.

Viewed from the side you may well, in a short-haired dog like a Boxer, be able to see a hint of the last few ribs if your dog is lean and fit.

There ought be an obvious tuck at the waist.

If he looks like a barrel from front to back when viewed from above, your Boxer is too fat.

Obesity is associated with many serious health problems including diabetes and joint problems.

Studies have shown caloric restriction confers some of the same but not all of the protective benefits as fasting.

A lifetime study that restricted calories to 70 per cent of a normal diet in Labrador Retrievers showed a decreased incidence and severity of osteoarthritis and a two-year increase in lifespan.

What does this mean for your dog?

As well as periods of total fasting, it’s good practice to slightly underfeed your dog.

Slight underfeeding of puppies is advised by raw feeding veterinarian and dog breeder Dr Ian Billinghurst, who says he’s consistently seen pups do better when their growth is “held back” by giving them less, rather than more, food.

There is no excess in nature.

But your Boxer doesn’t have to be visibly overweight to be consuming too much fat.

Signs of fat overconsumption or overfeeding include:

Fat is on a continuum with toxins.

In other words, when your Boxer’s body is overburdened with waste as a result of fat overconsumption, it creates its own toxic load.

In the short term, this manifests as the above symptoms.

Prolonged fat overconsumption plays into the disease process responsible for myriad chronic health problems.

Fasting can both reduce overall dietary fat consumption and support the body to clear any backlog of waste.

9. Fasting Can Lengthen Your Boxer’s Life

The cellular repair and regeneration achieved via autophagy has a key role in preventing many of the conditions that shorten Boxers’ lives such as:

  • Cancer
  • Neurodegenerative diseases (including dementia and Parkinson’s in humans)
  • Cardiomyopathy
  • Diabetes
  • Liver disease
  • Autoimmune diseases
  • Infections
  • Neuropathies (disease or dysfunction of peripheral nerves causing numbness/weakness)

While wild dogs benefit from autophagy on account of regular fasting, this process is disrupted in the great majority of Boxers, as well as most of the pet dog population.

A lack of fasting, combined with other mistakes in care and feeding, may well go a long way towards explaining the disease we see in our dogs.

How To Fast Your Boxer

You can integrate fasting into your dog’s routine as both a preventive health strategy and a go-to response whenever your dog is unwell.

If you currently feed two or three meals a day to an adult Boxer, you might start moving in the right direction by feeding just one meal, or two meals close together.

By splitting the daily food intake into two smaller meals but feeding them both within a six hour window at the same end of the day you can minimize bloat risk and maximize digestive rest.

To get your Boxer’s body into a fasted metabolic state, you need to withhold food for at least 24 hours i.e. feeding once per day is not incorporating a fast day, it’s just once daily feeding.

Always make sure fresh, pure water is freely available.

Fasting once a week is a good place to start.

To truly harness the benefits of fasting for your Boxer, including a three day fast on a regular basis is worthwhile.

Owners who embrace fasting might feed every second day or feed several days in a row and then fast for a few days.

There doesn’t need to be any set schedule — the availability of prey is what dictates when a dog eats in the wild, and so the routine varies.

If you are not yet raw feeding your Boxer, a 24 hour fast is the perfect full stop behind kibble and other processed food, before commencing the #1 best food for Boxers: a fresh, natural canine diet.

As discussed earlier, if your Boxer is sick or showing symptoms of some kind, a good rule of thumb is to fast for 24 hours initially, or until symptoms resolve.

Nora Lenz, the author of Canine Nutrition 101 and proponent of the style of raw feeding known as rotational monofeeding has had a lot of success clearing UTI-type symptoms with a two or three day fast.

Some Cautions About Fasting And Your Boxer

Fasting may not be suitable for:

  • Puppies less than a year old
  • Boxers on medication

Medicated dogs may not be able to fast, either because the meds must be given with food or because of the way the drugs interfere with the body’s ordinary functioning.

Fasting will, however, be a valuable tool in detoxifying the body after medication is discontinued.

Be sure to approach fasting carefully in dogs that have previously been heavily medicated/vaccinated as it can trigger strong detox. The toxins are better out than in, but the getting there can be unpleasant.

Fruit-only days can be used in lieu of fast days.

As facultative carnivores, fruit is a natural secondary food for dogs.

A wide variety of fruits can be fed to your Boxer.


There are actually many more than nine reasons to fast your Boxer.

Through its health-promoting effects, fasting will extend your Boxer’s lifespan.

Thanks to its ability to resolve symptoms, without administering toxic drugs like Benadryl and prednisone that can create dangerous side effects, it will save you money on vet bills.

Fasting is a free, and freely available healing modality that is safe, natural and effective.

Once you see the effect on your Boxer, you may even begin fasting yourself once in a while!


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