Depending on who you ask, the term leaky gut might fall into the same category as magic potions and balancing chakras. However, there is a growing body of scientific literature showing that increased intestinal permeability is closely linked to a huge range of diseases. Although there is no real difference between the two terms, you may get fewer scowls or eye rolls if you use the term "increased intestinal permeability" when speaking to your friendly local medical professional. 

We speak both languages and spend a lot of time addressing both leaky gut and increased intestinal permeability with our patients. 

Hippocrates made this statement more than 2,000 years ago, but it is only recently that we have come to understand that he was absolutely correct. As we have mentioned in other posts, the health of your gut (i.e. your intestinal tract) is absolutely critical to your overall health and wellbeing. Poor gut health contributes to a variety of disease including diabetes, obesity, rheumatoid arthritis, autism spectrum disorder, depression, and chronic fatigue syndrome to name a few. 

What is leaky gut?

If you think about it, everything that's in your gut/digestive tract is technically still on the outside of your body. Think about human bodies as being shaped like a donut with a hole in the middle running from the mouth to the anus. This hole is the inside of your gut. Nothing that is in your gut is actually part of your body. 

The cells that line your gut are supposed to let the good guys in (like water and nutrients) and keep the bad guys out (toxins, viruses, and undigested food). 

Proper function of your gut barrier depends on two things. The actual physical lining of the gut as well as the "functional" barrier which consists of chemical secretions, proteins, and other substances that don't form an actual physical barrier but still keep undesirable substances out. 

The barrier of the gut is part of the digestive system and it determines what nutrients get into your body to be use for energy. It's also part of the immune system because it keeps things like viruses and toxins out. 

This study looks and how your gut does all of these things at the same time. 

Leaky gut or increased intestinal permeability occurs when the barrier of your gut doesn't work properly. When this happens, large protein molecules are allowed out of your gut and into your bloodstream. Since these proteins are supposed to remain inside your gut (or outside your body), the body's immune system attacks them. There are studies showing that these attacks play a part in the development of autoimmune disease such as Hashimoto's and even type 1 diabetes. 

Study: Integrity of gut barrier is a major factor in autoimmune disease.

The part of this that is important is that the gut barrier seems to generally determine whether we react to a toxic substance or not. Also, when these substances enter the blood stream from the digestive system (which is only possible if you have a leaky gut), the immune response that occurs affects both the gut and other organs and tissues. This is important to understand because it means that you don't need to have digestive symptoms in order to have a leaky gut. 

What are leaky gut symptoms?

Gastrointestinal Symptoms

• Abdominal Pain
• Bloating
• Irregular stools (constipation or diarrhea)
• Reflux/heartburn
• Burping
• Gas
• Nausea/vomiting

Skin Symptoms

• Acne
• Dry skin
• Rashes
• Hives
• Psoriasis
• Eczema
• Rosacea
• Itchy Skin

Neurological Symptoms

• Fatigue — especially after eating
• Brain Fog
• Headaches
• Anxiety
• Depression
• Insomnia
• ADD/ADHD

Other Symptoms

• Joint Pain
• General aches and pains
• Multiple food sensitivities/allergies
• Autoimmune Disease
• Difficulty maintaining a healthy weight
• Symptoms of malnutrition

What causes a leaky gut?

There is a protein called zonulin which has been shown to increase intestinal permeability in humans. It is also well documented that most autoimmune diseases are characterized by abnormally high levels of zonulin and a leaky gut. In animal studies, researchers found that they could induce type 1 diabetes almost immediately in animals by exposing them to zonulin. 

One of the very first dietary changes we recommend to patients who we believe to be suffering from a leaky gut (which, honestly, is almost everyone) is to eliminate wheat and other gluten-containing grains. Why? Because they contain a protein called gliadin which increases zonulin production and therefore may be directly responsible for leaky gut. 

What else causes leaky gut? Unfortunately, there are many triggers and for most people it is likely a result of a variety of causes.

• Stress. Chronic stress is especially at fault as it increases intestinal permeability. But acute (short-term) stress can do the same. For example, serious burns can contribute to leaky gut. 
• Systemic inflammation. If your diet is full of seed oils, refined sugar, or other processed food, if you are exercising too much, or if you aren't sleeping enough you are at risk for developing leaky gut. 
• Some medications such as NSAIDs, like ibuprofen, increase intestinal permeability.
• Anything that upsets the balance of gut flora (e.g. antibiotics) should also be a suspect, although the precise effect depends on specifically what it does to unbalance or harm gut flora. 

Vitamin D is another component in developing and preventing leaky gut. Vitamin D is important in immune function, but it is also important in protecting the lining of the intestines. In a study done on mice, researchers found that vitamin D strengthened the cells in the intestinal lining against infections that are known to increase intestinal permeability. While this is not a direct cause, it appears that vitamin D deficiency increases the likelihood of developing leaky gut in the presence of certain infections. 

While there is a test for leaky gut (the lactulose/mannitol test), it is not covered by insurance and can be very expensive, so we tend to diagnose patients with this condition based on their symptoms. 

Healing and restoring gut function

While healing your gut and restoring optimal gut function does take a little work on your part, most people are amazed at how great they feel after a few simple changes to optimize gut function. Many of their symptoms disappear completely and they often can't believe that their guts were responsible for making them feel so miserable in the first place. 

1. Eat well

The first step, and sometimes the hardest, in healing a leaky gut is to remove the potential triggers such as gluten, refined/processed foods, trans fats. Eating whole fruits and vegetables with plenty of protein and healthy fats is a critical step in recovering the integrity of the intestines. 

There are some supplements that may help to decrease gut permeability and improve the gut microbiome:

Whey protein

L-Glutamine

Saturated Fat

Omega 3 fatty acids

Bifidobacterium bifidum

Whole food options that contain many of these beneficial supplement components are (because it's always better to get what you need from food, but sometimes you need to supplement): wild-caught, cold-water fish, fermented foods like sauerkraut, organic raw whole dairy, pastured lard/ghee/butter, and bone broth.

2. Be smart with exercise

Exercise is beneficial for many reasons, it increases muscle strength, improves mood, and can potentially slow aging. However, if you find that you are participating in long periods of high-intensity exercise, rest would be better. 

In a study done on rats, 60 minutes per day of exercise for 10 days at 70% of maximum effort improved antioxidant levels, tight junctions in the gut, and reduced overall inflammatory markers. This doesn't directly correlate to humans, but a similar exercise regimen would likely produce similar results. 

3. Sleep well

Sleep is extremely important. Optimizing sleep when you are recovering from any illness is also important. Although the amount of sleep required by individuals varies, you should aim for a minimum of seven hours each night. It may not seem like sleep would play an important role in gut healing, but it reduces metabolic stress and may even allow our organs to synchronize. 

Check out the blog post Sleep and Disease Risk for tips on improving your sleep

In addition to these tree steps, you may need to address any intestinal pathogens. We strongly recommend that you work with a provider to address your leaky gut, especially if you require medication to treat any chronic infections. 

While leaky gut might sound like a silly disease that someone made up, you can see that it can be the cause of some very serious health concerns.  Letting nutrients in while keeping everything else out is a hard job and if the system your body has for doing that gets off balance, it can cause some very serious  inflammatory and autoimmune issues down the line. Don't wait until you feel terrible to address this issue!