This Dr. Axe content is medically reviewed or fact checked to ensure factually accurate information.
With strict editorial sourcing guidelines, we only link to academic research institutions, reputable media sites and, when research is available, medically peer-reviewed studies. Note that the numbers in parentheses (1, 2, etc.) are clickable links to these studies.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
This article is based on scientific evidence, written by experts and fact checked by our trained editorial staff. Note that the numbers in parentheses (1, 2, etc.) are clickable links to medically peer-reviewed studies.
Our team includes licensed nutritionists and dietitians, certified health education specialists, as well as certified strength and conditioning specialists, personal trainers and corrective exercise specialists. Our team aims to be not only thorough with its research, but also objective and unbiased.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
What Kind of Leaky Gut Test Should You Take?
August 1, 2017
Think you might have leaky gut syndrome, causing you to experience symptoms like arthritis, fatigue, headaches and mood changes? If so, you should strongly consider taking a leaky gut test.
Many health and nutrition experts agree that to a large extent, health really begins in your gut. Why? A large portion of your immune system actually resides within your gut (about 75–80 percent), where billions of bacteria live (both good and bad). Your gut communicates with your brain to control things like appetite, mood and stress levels — plus it helps control your body’s ability to defend itself from sickness.
When your gut is healthy, it remains tightly “sealed,” in essence, carefully keeping toxins and waste within the digestive tract where they belong instead of spreading throughout your body.
Leaky gut syndrome, a condition that occurs when the gut lining becomes abnormally permeable (known as “intestinal hyperpermeability”), is diagnosed (through a leaky gut test) when tiny gateway openings develop between your intestines and bloodstream, allowing things to pass through that are normally blocked — like toxins, undigested food particles and other harmful substances.
- Autoimmune reactions and diseases
- Inflammatory bowel disease (including IBS and ulcerative colitis)
- Learning disabilities, like autism
- Food allergies or sensitivities
- Asthma
- Skin disorders like eczema and psoriasis
- Arthritis and other body aches or pains
- A higher chance for developing diabetes
- Fatigue
- Changes in mood, weight and appetite
How to Test for Leaky Gut Syndrome
The first step to healing leaky gut syndrome is to identify if you’ve developed the condition through a leaky gut test, which is important because the symptoms of leaky gut often are wrongly attributed to many other health conditions. Here are four tests I recommend you complete to determine if you’re experiencing leaky gut syndrome.
1. Zonulin or Lactulose Tests
Why It’s Important:
Zonulin controls the size of the openings between your gut lining and your bloodstream. Even in healthy people, small openings are needed between the two to transport nutrients back and forth, but abnormally high levels of zonulin can cause these openings to become too large.
What triggers zonulin levels to rise? Most often, gluten, parasites, candida yeast and harmful bacteria do. A leaky gut test can reveal how high zonulin levels are, which gives you a good idea of your gut permeability. It’s important to correct zonulin levels right away because over time, even more damage occurs in the gut’s “microvilli,” the tiny cellular membranes that line the intestines and absorb nutrients from food. (1)
How This Leaky Gut Test is Done:
Using an enzyme-linked immunosorbent assay test (ELISA), serum levels of zonulin can be tested to serve as a biomarker of how much intestinal permeability there is. More information on ELISA tests can be found here.
An intestinal permeability assessment can also measure the ability of two sugar molecules to permeate the gut lining — lactulose and mannitol. This leaky gut test checks for levels of the two sugars present in the urine from a sample collected over the six hours after ingesting them.
2. IgG Food Intolerance Test
Why It’s Important:
You need to identify any food sensitivities you have if you think you have leaky gut, since most people who have leaky gut wind up developing sensitivities as a result — and ignoring these can make the condition even worse.
Why does leaky gut cause sensitivities and food allergies? When particles and toxins enter the bloodstream that normally shouldn’t be able to, the immune system basically goes on “overdrive,” working hard to do what it thinks is beneficial for the body by raising immune responses. Intestinal hyperpermeability makes the body produce a high level of antibodies, with the hope of defending the body from dangerous particles.
This means the immune system is extra cautious and reactive, so it tends to negatively respond to foods that it used to tolerate better, especially things like gluten and pasteurized dairy.
While some food sensitivities or reactions are obvious, others are more subtle and can easily go unnoticed, since they produce what’s known as “low-grade systemic inflammation.” This becomes dangerous over time and can cause a range of inflammatory diseases, so removing food sensitivities is critical to getting leaky gut under control.
How This Leaky Gut Test is Done:
The IgG Food Allergy Test (either with or without Candida testing) is available as a dried blood spot collection. You can either have the leaky gut test done by having blood drawn or by using dried blood that can be collected from home and shipped to a laboratory for analysis. More information on having a igG food intolerance test done can be found here.
3. Stool Tests
Why It’s Important:
A stool test looks at beneficial bacteria levels, the state of intestinal immune function, overall intestinal health and inflammation markers.
Additionally, fecal matter can reveal probiotic levels along with microbes present in the gut, both the good kind and the bad. It also reveals information about any pathogenic micro-organisms, such as yeast, parasites and bacteria that might contribute to leaky gut, chronic illness and neurological dysfunction (like mood changes or “brain fog”).
How This Leaky Gut Test is Done:
Collect stool samples at home in private, and then mail them to a lab. Stool samples must be collected on two separate days (at least 12 hours apart) and sent to a lab for testing within 10 days of being collected.
Before collecting the sample, you must stop consuming most supplements (digestive enzymes, antacids, iron supplements, over 250 milligrams of vitamin C, aspirin, anti-inflammatories) and remove or limit the amount of meat you eat during the 48 hours prior to the collection. More information on having this leaky gut test done can be found here.
4. Organic Acid Vitamin and Mineral Deficiencies Tests
Why It’s Important:
One of the common warning signs of leaky gut is nutrient malabsorption or vitamin/mineral deficiencies. This occurs because of damage to the gut’s microvilli. When microvilli stop working properly, it’s possible for large particles to pass through the gut lining that shouldn’t (like gluten) and for some small molecules to be blocked that are actually meant to pass through and provide nutrients.
Another downside of blocked or malabsorbed nutrients is that they can’t help with detoxification of antigens that the immune system produces at high levels in response to leaky gut.
An organic acid test looks for vitamin and mineral deficiencies; amino acid (protein) deficiencies; information in regard to protein, fat and carbohydrate metabolism; and antioxidant and bacteria levels.
How does it work? Organic acids are produced during central energy production, detoxification, neurotransmitter breakdown or intestinal microbial activity. When they accumulate to high levels, they can be detected in urine and signal a nutrient deficiency, problem producing digestive enzymes, yeast growth or toxic buildup.
How This Leaky Gut Test is Done:
Organic acids tests help identify nutritional deficiencies by looking at the effects of the nutrient deficiencies as byproducts that occur. This is believed to be much more accurate, effective and reliable than just looking at nutrient levels. It can also tell you how well your body uses nutrients, plus information related to leaky gut, such as bacteria and probiotic levels.
This leaky gut test is a simple kit that you can perform at home, so a doctor visit isn’t necessary. You’re mailed a kit to collect your urine sample and then mail it back to a lab where tests are performed. More information on organic acid tests can be found here.