Is Your Digestion Bulletproof – Or Do You Have Leaky Gut?

Bulletproof Leaky Gut and Digestion

The Bulletproof diet is by design a very low inflammation diet, and this is perfect for addressing gut issues like intestinal permeability AKA “leaky gut”. Also, the other lifestyle aspects of living bulletproof like optimising sleep, reducing stress and reducing environmental toxins is also important when addressing any health issue, including digestion problems.

What is Leaky Gut?

This is a term that has been talked about by naturopaths and alternative health practitioners for many years, and for a long time, the idea that the gut could leak toxins and bacteria into your bloodstream was dismissed by conventional medicine. However, this is all changing over the last 5 years since Dr Alessio Fasano’s groundbreaking research, which confirmed the connection between leaky gut and autoimmune conditions.

Dr. Fasano also showed the mechanism with how leaky gut occurs, a protein called Zonulin regulates the permeability of the tight junctions between the cell walls of the intestine. Zonulin is an important protein to have, but excess levels lead to leaky gut and an increased risk of many health conditions.

From your mouth to your anus the gastrointestinal tract is basically one long winding tube, the contents of the gastrointestinal tract are considered to be “outside” the body. It is the role of your digestive system to break down this food into simple sugars, fatty acids and amino acids, which along with vitamins, minerals and other nutrients you absorb through the gastrointestinal wall. The rest of the waste material continues along the rest of the digestive tract to be eliminated.

Leaky gut occurs when the intestinal wall becomes more permeable, which allows larger food particles, proteins and lipopolysaccharides to cross the intestinal wall and enter your blood stream. These toxins can create inflammation, which is one of the driving causes behind many diseases. Your immune system can create antibodies against them and this can be a trigger for autoimmune disease.

What Causes Leaky Gut?

The initial research that showed Zonulin was the mechanism to cause intestinal permeability used gluten to trigger the reaction, the Zonulin levels are much greater in celiacs but are also elevated in people without celiac disease after eating gluten. Other factors can increase Zonulin levels which I have listed below.

Causes of leaky gut include:

  • Gluten containing grains.
  • Processed food diet high in sugars and industrially processed oils.
  • Parasite, bacterial and yeast infections, in particular in the small intestine.
  • Alcohol, especially if there is already inflammation or infections present.
  • Mould infections.
  • Heavy metals.
  • Medications like NSAIDS and other pain killers, antibiotics and steroids.

So even if you are eating a Bulletproof diet, but have an undiagnosed gut infection, or you are still being exposed to moulds, there is a good chance you may have leaky gut.

Symptoms of Leaky Gut

The symptoms of intestinal permeability can be wide and varied. In fact, you can have leaky gut without actually having any digestion symptoms. However if you have chronic digestive symptoms like diarrhoea, constipation, bloating and excess gas there is a good chance you may have leaky gut.

Dr. Alessio Fasano has done a lot of research into leaky gut and autoimmune conditions, and has made the statement that “you cannot have an autoimmune condition without first having leaky gut.”

Symptoms of leaky gut include:

  • Chronic diarrhoea, constipation, gas or bloating – even when you are eating Bulletproof.
  • Nutritional deficiencies – especially iron, B12 and zinc.
  • Poor immune system – frequent colds and taking a long time to recover.
  • Headaches, brain fog, memory loss – finding it hard to focus and remember easy things.
  • Excessive fatigue – this can be caused by many things and a good place to start is gut function.
  • Skin rashes and problems such as acne, eczema or rosacea – often caused by gut issues.
  • Cravings for sugar or carbs – especially if you have a candida or bacteria overgrowth.
  • Arthritis or joint pain – dressing gut function can reduce systemic inflammation.
  • Depression, anxiety, ADD, ADHD – there is a lot of research between gut function and mood.
  • Autoimmune diseases such as rheumatoid arthritis, lupus, celiac disease or Crohn’s – a lot of evidence that these conditions are triggered by infections and gut permeability.

Address the Cause

Eating a Bulletproof diet is a good place to start, especially if you include gut healing foods such as bone broth, but it is important to address the underlying cause of your gut problems in the first place, especially if symptoms persist.

The best place to start is with a Comprehensive Digestive Stool Analysis (CDSA) test, a CDSA test can detect underlying bacteria, parasite and yeast infections that maybe the driving force behind your gut problems. A good CDSA test will also include your levels of beneficial bacteria, simply not having enough of the good “bugs” can allow commensal and pathogenic bacteria to take over your digestive tract.

I would also recommend a CDSA test that includes testing for Zonulin, this can help you identify if you have leaky gut, and how severe it may be, which can help with planning your treatment.

SIBO testing is another option, Small Intestinal Bacteria Overgrowth (SIBO) damages the microvilli of the small intestine leading to increasing intestinal permeability. This is why SIBO infections can cause a wide range of health problems.

Once you have addressed the cause this allows the healing process to take place, the good news is that there is a high turnover of cell and cell regeneration in your intestines. This allows your gut to heal, this will quickly lead to an improvement not only in digestion function but your overall health.


Here are the steps that I recommend if your gut health is not optimal:

  1. Eat a Bulletproof diet or a low FODMAP version of the Bulletproof diet to assess if there are any food triggers that are the cause of your symptoms.
  2. If digestion or other health problems persist get a CDSA test that also includes Zonulin and possible also test for SIBO.
  3. Address any infections or lack of beneficial bacteria.
  4. Eat plenty of gut-healing nutrients like bone broth, collagen, glutamine, curcumin and specific probiotics to restore gut health.


Michael Smith is a Naturopath and Functional Medicine Practitioner at Planet Naturopath. Specialising in hormonal disorders, adrenal, thyroid and digestive function, Michael works with clients from the chronically ill to athletes wanting to improve performance. Consultations are available via Skype or phone and the functional pathology testing is available throughout Australia.