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The Gut-Weight Connection: How Healing Your Digestion Can Help You Lose Stubborn Pounds

Jenna Johnston on January 8, 2025

When it comes to weight loss, the advice often centers around cutting calories, hitting the gym, or avoiding carbs. But if you’ve been following all the “rules” and still aren’t seeing results, it’s time to shift the focus—from your plate to your gut.

Your gut isn’t just responsible for digesting food; it plays a central role in regulating your metabolism, hormones, inflammation, and even your ability to lose or gain weight. What’s more, it’s not just about having the “right” balance of gut bacteria—your gut lining also plays a critical role in determining how your body processes nutrients and stores fat.

In this article, we’ll explore the gut-weight connection, why digestion is foundational to sustainable weight loss, and how healing your gut can help you finally shed stubborn pounds.

Understanding the Gut-Weight Connection

What Is Gut Health?

Gut health refers to the balance of microbes (bacteria, fungi, and viruses) living in your digestive tract and the strength of the gut lining itself. These two elements work together to ensure proper digestion, nutrient absorption, and protection from harmful substances.

A healthy gut is key to:

  • Reducing systemic inflammation.
  • Regulating hunger hormones.
  • Supporting metabolism and detoxification.

But when the gut is out of balance—either due to dysbiosis (an imbalance of good and bad bacteria) or a compromised gut lining—your body can struggle to maintain a healthy weight.

How Poor Gut Health Impacts Weight

  1. Inflammation: An unhealthy gut can trigger chronic inflammation, which makes your body resistant to weight loss. Inflammation interferes with your hormones and can increase insulin resistance, encouraging fat storage.
  2. Hormonal Imbalances: Your gut influences hormones like cortisol, estrogen, and leptin. Cortisol, your stress hormone, can promote belly fat when elevated. Estrogen imbalances, often linked to poor gut health, also make weight loss challenging.
  3. Gut Dysbiosis: Certain gut bacteria are more efficient at extracting calories from food, meaning they can increase fat storage even when you’re eating the same amount as someone with a healthier microbiome.
  4. Leaky Gut: When the gut lining is weakened, toxins and undigested food particles can leak into the bloodstream, triggering inflammation and metabolic disruption. This can lead to systemic issues that further block weight loss efforts.

Common Gut Issues That Affect Weight Loss

Here are some gut-related factors that could be blocking your weight loss:

  • Slow Digestion or Constipation: Impaired motility can lead to toxin buildup, increased bloating, and hormone imbalances.
  • Overgrowth of Bad Bacteria: Dysbiosis can disrupt hormone signals and lead to increased sugar cravings, making it harder to maintain a healthy diet.
  • Compromised Gut Lining: A weakened gut lining (leaky gut) affects your immune system and makes it difficult for your body to process nutrients effectively.
  • Poor Detoxification: The gut and liver work in tandem. If gut health is poor, detoxification processes can become sluggish, which impacts hormone balance and fat storage.

How to Heal Your Gut for Weight Loss

Start with Functional Testing

Healing your gut begins with understanding what’s happening inside. Functional testing, such as the GI-MAP test, offers a comprehensive look at your gut health. This test reveals bacterial imbalances, markers of inflammation, leaky gut, and even parasitic or fungal infections.

By identifying these root issues, you can develop a targeted and personalized protocol rather than relying on guesswork. A GI-MAP test ensures that every step you take is precise, effective, and tailored to your unique needs.

Make Dietary Changes

  1. Add Fiber: Increasing your intake of fiber-rich foods like vegetables, low-glycemic fruits like berries, and seeds (like chia or flax) is crucial for gut health. Fiber feeds beneficial bacteria, promotes regular digestion, and helps balance blood sugar.
    **Important Note: If you’re increasing fiber, ensure you’re also drinking enough water—at least 2.7 liters per day for women. Without adequate hydration, additional fiber can worsen constipation or even cause it. Staying hydrated ensures your digestion remains smooth and effective.
  2. Incorporate Prebiotics and Probiotics: Foods like garlic, asparagus, sauerkraut, and yogurt support a balanced microbiome. Prebiotics feed your beneficial bacteria, while probiotics replenish them.
  3. Reduce Inflammatory Foods: Cut back on sugar, processed foods, and refined carbs. These foods disrupt gut bacteria and contribute to inflammation, making weight loss harder.
  4. Support Your Gut Lining: Nutrients like glutamine, zinc carnosine, and collagen (found in bone broth) help repair and strengthen the gut lining, reducing inflammation and improving nutrient absorption.

Adopt Lifestyle Adjustments

  • Manage Stress: Chronic stress weakens the gut lining and disrupts the microbiome. Incorporate stress-reducing practices like yoga, meditation, or even a 10-minute walk outdoors.
  • Prioritize Sleep: Poor sleep impacts your gut bacteria and digestion. Aim for 8-10 hours of restorative sleep to support weight loss and overall health.
  • Regular Movement: Gentle exercises like walking or Pilates promote gut motility, reduce inflammation, and support a healthy nervous system.

Targeted Supplements

Supplements can be an essential part of a gut health protocol, but they need to be chosen carefully. Not all supplements are created equal, and not every supplement is suitable for every person. Working with a nutritionist who knows what to look for—or leveraging insights from functional testing like the GI-MAP test—ensures you’re selecting the right supplements for your unique needs.

Here are some targeted supplements that can make a difference:

  1. Digestive Enzymes: Aid in breaking down food more effectively, preventing bloating and discomfort.
  2. Probiotics: Replenish beneficial bacteria and help balance your gut microbiome. Choose strains targeted to your specific needs, such as Lactobacillus rhamnosus for gut inflammation or Bifidobacterium breve for better digestion.
  3. Herbal Remedies:
    • Berberine: Helps combat bacterial overgrowth and supports blood sugar regulation.
    • Digestive Bitters: Stimulate digestive enzyme production and bile flow.
    • Peppermint Oil: Soothes gut discomfort and reduces bloating when taken in an enteric-coated capsule.
  4. Glutamine: Helps repair and strengthen the gut lining, reducing inflammation and improving absorption.

The right supplements can make a HUGE difference and help address specific deficiencies or imbalances, but they should complement—not replace—foundational strategies like diet and lifestyle changes.

Why Sustainable Weight Loss Starts in the Gut

Healing your gut is more than a weight-loss strategy—it’s the foundation for long-term health. By addressing gut inflammation, balancing hormones, and supporting your microbiome, you’re giving your body the tools it needs to thrive.

When your digestion is functioning optimally:

  • Inflammation decreases.
  • Hormones regulate more effectively.
  • Hunger and satiety signals become more reliable.
  • Energy levels improve.

The result? Weight loss becomes more sustainable, and your overall health improves dramatically.

Conclusion

If you’ve been struggling with stubborn weight gain despite your best efforts, it’s time to shift the focus to your gut. Healing your digestion allows you to address the root causes of weight struggles and build a foundation for long-term health.

Functional testing like the GI-MAP test provides invaluable insights into your gut health, helping you create a personalized plan that works. At Jenna Johnston Functional Nutrition, I specialize in helping clients heal their gut, balance their hormones, and achieve lasting results. Let’s take the first step toward your health goals—together.

Book a FREE Discovery Call today to learn more about working with me.

Postpartum Candida Overgrowth: Causes & Natural Solutions for a Common Concern

Jenna Johnston on May 19, 2023

Candida overgrowth has become a common health concern and I’ve seen it over and over again in my patients struggling with chronic symptoms during the postpartum years and beyond. The likely reason for this is that pregnancy and the postpartum period can increase the risk of candida overgrowth due to several factors. And if the issue is left untreated and factors that contribute to the overgrowth are left unchanged, then the candida overgrowth can end up leading to a number of complex health issues.

What is candida overgrowth?

Candida is a fungus (i.e., a form of yeast) that is naturally found in small amounts in the mouth, intestines, skin, and vagina. In the digestive tract and mouth, it aids in the digestion of food and absorption of nutrients when it’s in proper amounts. It’s considered a normal part of the body’s microbiome which is the collection of various microorganisms such as bacteria and yeast that live in different areas such as the gut, mouth, skin, vagina, sinuses, and throat.

When the microbiome is in a healthy, balanced state, the different microorganisms keep each other in check and issues are less likely to arise. However, if the balance is disrupted, opportunities arise for certain microorganisms to overgrow- such as candida. The most common type of candida is Candida albicans.

When candida is overproduced, typical symptoms may appear such as vaginal yeast infections, vaginal or anal itching, white coating on the tongue, and/or thrush. If overgrowth occurs in the digestive tract and is left unchecked, it can lead to a fungal infection called Candidiasis and start to break down the walls or lining within the intestinal tract and end up in the bloodstream. 

Essentially, this leads to the release of toxic byproducts and other toxins created from the body trying to fight it off and from the fungus itself- leading to increased gut permeability or “leaky gut”. It also creates the perfect opportunity for bacterial biofilms to be created which is a protective slime for groups of microorganisms that makes it harder to control candida overgrowth. 

Moreover, undigested food particles can also leak into the bloodstream and people with candida overgrowth can start to develop new food sensitivities and allergies that they never had before, e.g., gluten, dairy, eggs, and corn. In addition to this, other symptoms can start to arise from an overgrowth of candida, such as those associated with mood, cognitive health, digestion, food cravings, immune function, skin, and more (which we’ll cover below).

Unfortunately, what happens is that candida overgrowths can end up leading to various biological changes in the body, such as reducing immune system function and altering the body’s pH levels (i.e., making it more acidic), which ultimately can make it more difficult to eliminate candida overgrowths without the right holistic treatments. 

Why is it common during postpartum?

In some individuals, candida overgrowth becomes more likely after pregnancy due to a number of different factors that create the perfect opportunity for candida to multiply.

  1. Hormonal changes
    During pregnancy, estrogen levels increase significantly, but after childbirth, there is a rapid drop in estrogen levels and it may stay low for up to 6 months or longer. This drop can lead to a shift in the composition of the microbiome of the gut and vagina which can create an environment that’s more favorable to candida overgrowth.

    Moreover, estrogen is known to have an immunoenhancing effect on the immune system and has been shown to regulate the immune response in various ways. This means that when estrogen is within normal levels, it helps to support a healthy immune system but when it drops too low, it may lead to immune system suppression. As a result, it may become more difficult for the immune system to fight off candida overgrowth.
  2. Antibiotic use
    Antibiotics are commonly prescribed during childbirth usually for Group B Strep to decrease the chances of passing this bacteria to the baby because it can cause serious infections. Antibiotics may also be given during postpartum for illnesses or infections such as mastitis.

    Unfortunately, antibiotics can cause disruption to the balance of beneficial bacteria in the gut, which can lead to candida overgrowth. And since postpartum is a more vulnerable time for mothers, the risk for candida overgrowth from taking antibiotics may be even higher.
  3. Reduced immune function
    The immune system is responsible for protecting the body against pathogens, including candida. When the immune system is weakened or suppressed, candida can overgrow more easily because the body is less able to fight off the fungus. This can happen in a variety of situations, including during periods of stress, or illness, or after taking certain medications such as antibiotics or immunosuppressive drugs. 

    In postpartum women, the immune system may be weakened due to the physical stress of giving birth, healing after birth, lack of sleep, and/or hormonal fluctuations, which can increase the risk of developing candida overgrowth.
  1. Nutritional deficiencies
    During the postpartum period, there is an increased demand for essential nutrients due to the physical demands of recovery and lactation. A deficiency in nutrients like vitamins A, C, D, and E, zinc, and selenium can impair immune function and compromise the body’s ability to fight off candida overgrowth.

    Inadequate intake of B vitamins, especially thiamine (B1), can also contribute to the development of candida overgrowth because thiamine is required for proper cellular energy production, including the energy required for the immune system to function effectively.

    Additionally, certain nutrients like prebiotics and probiotics play a crucial role in maintaining a healthy gut microbiome, which can help prevent candida overgrowth. A diet lacking in these nutrients can lead to imbalances in the gut microbiome, increasing the risk of candida overgrowth.

    Lastly, postpartum women may have difficulty consuming a balanced diet due to various factors like time constraints, sleep deprivation, and lack of access to healthy food options. This can lead to nutrient deficiencies that can increase the risk of candida overgrowth.
  1. Increased sugar consumption
    Increased sugar consumption can be driven by a number of factors. For one, the body has just gone through a significant physical stressor, and many women may find themselves reaching for sugary foods as a form of comfort or stress relief. Additionally, sleep deprivation and fatigue are common during this time, and the body may turn to sugar as a quick source of energy. Hormonal changes can also contribute to sugar cravings, as fluctuations in hormones like cortisol and insulin can impact blood sugar levels and lead to cravings for sweets.

    However, consuming large amounts of sugar can also create an environment in the body that is conducive to candida overgrowth. Candida is a type of yeast that feeds on sugar, and consuming too much sugar can cause an overgrowth of candida in the gut.
  1. Constipation and reduced gut motility
    When bowel movements are infrequent, it can lead to an accumulation of undigested food particles in the gut, providing a breeding ground for candida to thrive. Additionally, when the gut is not moving properly, it can compromise the immune system’s ability to regulate the growth of candida and other harmful microbes. This can allow candida to multiply and lead to overgrowth. Therefore, it is important to address any underlying digestive issues to prevent and treat candida overgrowth.

What are symptoms of overgrowth?

There are a variety of symptoms that can manifest from candida overgrowths that are very well known. Most people think of yeast infections when they picture candida overgrowths, but it can lead to many other issues that can affect various aspects of your health and parts of your body. 

Common candida overgrowth symptoms include:

  1. Anxiety, depression, mood swings, irritability, panic attacks- Excess yeast can impact neurotransmitter production such as serotonin and disrupt the delicate balance of chemicals in the brain, potentially leading to mood imbalances and emotional symptoms.
  2. Burnout, chronic fatigue, tiredness- Candida overgrowth can contribute to systemic inflammation and nutrient deficiencies such as magnesium, omega 3s, and B6- leading to fatigue, decreased energy levels, and overall feelings of exhaustion.
  3. Strong cravings for sugar and refined carbohydrates- Candida thrives on sugar and refined carbohydrates, and an overgrowth can create intense cravings for these foods as the yeast demands more fuel to sustain itself.
  4. Seasonal allergies and/or itchy ears- An immune response can be triggered by candida overgrowths, leading to increased sensitivity to allergens and potential symptoms such as itchy ears or seasonal allergies.
  5. Brain fog, issues with concentrating, ADD/ADHD, poor memory- High levels of candida can produce toxins that affect cognitive function, leading to symptoms such as brain fog, difficulty concentrating, ADD/ADHD-like symptoms, and impaired memory.
  6. Skin and nail fungal infections (e.g., toenail fungus, ringworm, athlete’s foot)- An elevated amount of yeast can disrupt the natural balance of microorganisms on the skin and nails, creating an environment conducive to fungal infections.
  7. Digestive issues (e.g., bloating, excess gas, constipation, diarrhea)- When the delicate balance of gut flora is disrupted it can lead to digestive symptoms such as bloating, excess gas, and changes in bowel movements.
  8. Autoimmune conditions (e.g., Hashimoto’s, psoriasis)- Candida overgrowth can contribute to systemic inflammation and compromise the immune system, potentially triggering or exacerbating autoimmune conditions.
  9. UTIs, vaginal infections, anal itching, or vaginal itching- Candida can disrupt the balance of microorganisms in the urogenital tract, leading to an increased risk of urinary tract infections, vaginal infections, and uncomfortable itching in these areas.
  10. Skin issues (e.g., rashes, eczema, psoriasis, hives): Candida overgrowth can trigger inflammatory responses in the body, potentially manifesting as skin issues like rashes, eczema, psoriasis, or hives. The overgrowth disrupts the natural balance of the skin microbiome, leading to these skin manifestations.

Candida can affect these various parts of the body because of its ability to break down the lining of the intestinal tract when it becomes overgrown in the intestines and causes a fungal infection called Candidiasis. This leads to “leaky gut” and candida can travel through the bloodstream and begin to invade other tissues such as the skin, ears, mouth, reproductive organs, thyroid, and other places.  

What are effective ways of getting rid of it? 

To eliminate candida overgrowth, a multifaceted approach is needed. It involves more than just stopping the growth and reducing the amount of candida- it also involves restoring a healthy balance of good bacteria that help to keep candida in check and repairing the gut lining to prevent candida from traveling through the gut. 

Step 1: Starve the candida

To starve the candida, it’s important to follow an anti-candida diet that eliminates simple sugars (e.g., cane sugar, coconut sugar, maple syrup, honey, etc.) dried fruits, fruit juices, fermented foods, gluten, inflammatory vegetable oils, and alcohol, and limits carbohydrates like fruits (only low-sugar fruits should be eaten like berries and citrus), legumes, non-gluten grains, and starchy vegetables like potatoes, sweet potatoes, winter squashes.  

Step 2: Reduce the amount

It’s important to increase the intake of foods and herbs that help to fight off the candida due to anti-fungal properties such as garlic, coconut oil, cloves, cinnamon, pau d’ arco, thyme, rosemary, oregano, and ginger. 

It’s also vital to use supplements and herbs to help break down the cell walls of the yeast and disrupt biofilms. These include herbs like garlic, plantain leaf, oregano, cinnamon, curcumin, and cranberry (for UTI-associated biofilms). And supplements like NAC (N-acetyl-cysteine), caprylic acid, EDTA (e.g., THER-BIOTIC® InterFase® Plus)

Step 3: Balance the microbiome 

Lastly, it’s important to balance the microbiome by repopulating it with friendly microbes that keep candida in check. Taking a probiotic that contains at least 100 Billion CFU and contains beneficial strains for controlling candida like Saccharomyces bouliardii, Lactobacillus rhamnosus, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus fermentum,  Lactobacillus acidophilus, and Bifidobacterium bifidum.

Conclusion

Candida overgrowth is a common issue that can wreak havoc on our health and well-being. It occurs when the balance of beneficial bacteria in our gut is disrupted, allowing the candida yeast to proliferate. The symptoms of candida overgrowth are diverse and can affect various systems in our bodies, including digestion, mood, and immunity. However, by taking proactive steps, you can reclaim your health and restore balance.

REFERENCES

Taneja V. Sex Hormones Determine Immune Response. Front Immunol. 2018;9:1931. Published 2018 Aug 27. doi:10.3389/fimmu.2018.01931

Otašević S, Momčilović S, Petrović M, Radulović O, Stojanović NM, Arsić-Arsenijević V. The dietary modification and treatment of intestinal Candida overgrowth – a pilot study. J Mycol Med. 2018;28(4):623-627. doi:10.1016/j.mycmed.2018.08.002

Ponde NO, Lortal L, Ramage G, Naglik JR, Richardson JP. Candida albicans biofilms and polymicrobial interactions. Crit Rev Microbiol. 2021;47(1):91-111. doi:10.1080/1040841X.2020.1843400

Richter A. (2022) 6 symptoms of candida overgrowth (plus how to get rid of it), Healthline. Available at: https://www.healthline.com/nutrition/candida-symptoms-treatment (Accessed: 19 May 2023).

Leaky Gut & Depression: Is There a Link Between Them?

Jenna Johnston on March 22, 2023

When we think about the cause of depression we often only think about an imbalance of neurotransmitters in the brain. However, new research is beginning to uncover a whole-body connection to depression and gut health may be one of the most important connections. 

More specifically, research has found a link between increased intestinal permeability (i.e. “leaky gut”) and an elevated risk for depression. Knowing more about what a leaky gut is, how it’s related to depression, and what we can do to “seal up” holes or cracks in the gut may be a key component in reversing depression in individuals who struggle with this condition.

What is “leaky gut”? 

Our intestines, which are a part of the gastrointestinal tract (GI tract) beginning after the stomach, are shaped like a tube and have walls or barriers that help to regulate the absorption of nutrients, water, and electrolytes from within the intestines into the body’s circulation. They also help to prevent the entrance of large or undigested food particles, toxic substances, and pathogenic microorganisms into the body.[1]

The intestinal barrier is formed by epithelial cells and a mucus layer that are joined together by proteins called tight junctions. Tight junctions help to regulate what passes into the body from the intestines, but unfortunately, certain conditions can disrupt this system. These junctions can become loose which creates larger openings for unwanted or harmful substances to enter or “leak” into the body.[1]

What causes leaky gut?

The cause of leaky gut isn’t cut and dry. There seem to be many potential reasons and research is ongoing. And many times researchers are left wondering what came first- the leaky gut or the issue related to it. So it’s a bit of a chicken and egg situation. 

However, there are some causes that seem to be well supported by research:

  1. Disruption in the microbiome 
    One important function of the gut microbiome is to develop and maintain the gut barrier throughout our lives.[1] However, disruptions in the microbiome at any point in life from genetic and/or environmental factors (e.g. diet, antibiotics, medications, allergens, stressors, toxins, heavy metals, infections, etc.) can disrupt the integrity of the gut barrier and increase permeability.[1][2]
  1. Food allergies or sensitivities 
    Some individuals have food allergies and/or sensitivities which means they react to certain foods and dietary proteins as if they were toxic or pathogenic. This causes an immune response and leads to inflammation of the mucosal barrier. In turn, this can lead to changes in the formation and function of tight junction proteins within the intestinal wall and lead to a leaky gut.[3]

    A common example of this is Celiac disease which is caused by a gluten allergy. Celiac disease is known for causing structural changes in the small intestinal wall, allowing unwanted substances to leak into the body.[3] 
  1. High blood sugar
    High blood sugar levels or hyperglycemia have been shown to increase intestinal permeability both in mice and human studies.[4][5] This results from the negative impact high blood sugar levels have on the genes expressed by epithelial cells that are involved in maintaining tight junctions in the gut- leading to a decrease in gut barrier integrity.[5]  
  1. Psychological stress
    Studies on humans have shown that situations that cause acute stress can affect gut permeability. For example, when individuals are exposed to public speaking-based stressors, researchers found that small intestinal permeability was significantly elevated but only in individuals who also responded to the stressor with a significant increase in cortisol.[1][6] 
  2. Circadian rhythm disruptions
    The circadian rhythm is the name for the various biochemical processes in our body that follow a roughly 24-hour cycle to regulate normal functions and behaviors. There is a “master body clock” found in the brain and “peripheral body clocks” found in organs (e.g. gut, pancreas, liver). They all need to be working in sync to keep everything they regulate on schedule.[7]

    When disruptions in your circadian rhythm occur such as those seen in shift workers (or parents with babies)- due to abnormal sleep, light exposure, and eating patterns- this has been shown to increase the likelihood of developing a hyperpermeable gut.[7]
  1. Low vitamin D levels
    Studies have found that low levels of vitamin D increase intestinal permeability. However, vitamin D supplementation improves the function of the gut barrier by reducing permeability by modulating the amount and distribution of tight junction proteins.[8]

How are leaky gut & depression linked?

Studies have found that individuals with major depressive disorder have elevated levels of various immune-inflammatory markers when compared to healthy control groups.[9] One reason for an increase in inflammation in these individuals might be due to an increase in intestinal permeability since it’s believed to play a major role in chronic low-grade inflammation in a number of different inflammatory disorders including depression.[1] 

Leaky gut plays a role in inflammatory conditions because various substances from within the intestines including bacteria make their way out of the gut into the circulation and end up in places in the body where they shouldn’t be. When this happens, the immune system is triggered and this leads to inflammation.[9] 

In individuals with depression, one location where inflammation is seen is in the central nervous system (CNS). Inflammation in the CNS has been shown to also change the function and integrity of the blood-brain barrier (BBB)- which is similar in structure to the gut barrier. This can affect the BBB’s ability to prevent unwanted substances (e.g. pathogens, toxins, and chemicals) in the bloodstream from entering the brain- further increasing inflammation in the CNS and elevating the likelihood of CNS diseases and psychiatric conditions.[3]  

Moreover, research has found that the more severe the depression, the higher the inflammation and the greater the permeability of the gut barrier- with patients with a recent suicide attempt having the greatest increases in inflammation and permeability.[10] 

How to test for leaky gut 

Testing for leaky gut is a great way to get a better idea of whether or not it may be at the root of your depression. However, some of these tests can be expensive, so it may be beneficial to work with a Function Medicine or Nutrition Practitioner who can give you a better idea of which one(s) might be the best suited for you.

From a Functional Medicine approach, there are 5 tests that are often used to determine if someone is experiencing a leaky gut:

  1. Measuring Zonulin
    Zonulin is a protein that controls the size of the tight junctions and high levels can indicate that the openings are too large. Checking blood serum levels of zonulin using an enzyme-linked immunosorbent assay test (ELISA) can help determine if gut permeability is too high.  
  2. Intestinal Permeability Assessment 
    This test is an assessment of the small intestinal absorption and barrier function. The test measures the ability of two sugar molecules- lactulose and mannitol- to permeate the gut lining. Learn more here https://www.gdx.net/product/intestinal-permeability-assessment-urine 
  3. Organic Acid Test
    A common problem with a leaky gut is the malabsorption of nutrients which can lead to nutrient deficiencies. Organic acid tests can help to identify any nutritional deficiencies or issues with absorbing and using nutrients- including vitamins, minerals, protein, carbohydrates, and fats. They can also detect antioxidant, bacterial, and probiotic levels which can also be helpful information in relation to leaky gut. 
  4. Stool Test
    Stool tests can help to determine the different levels and types of bacteria in the gut, the state of immune function within the gut, and the overall health of the gut. As well as reveal any inflammation that may be occurring. Reviewing all of these factors can help us know the likelihood of someone having a leaky gut. 
  5. IGg Food Sensitivity Test
    Many individuals who have developed increased gut permeability have also developed food sensitivities. And, as mentioned earlier, food sensitivities may also be a cause of leaky gut or may provoke worsening of it. For this reason, testing for IGg food sensitivities can help someone get a better idea if they are experiencing a leaky gut.   

How to heal a leaky gut

In Functional Nutrition, there is a method for repairing a leaky gut called the 4R approach:

Step 1: Remove 

First, it is essential to remove the things that are having a negative impact on your digestive system. This often includes foods that are causing inflammation such as any food sensitivities or allergies, as well as highly processed foods and/or foods with unwanted additives, artificial flavors, colors, and preservatives. This would also include removing any infections in the GI tract. 

Step 2: Replace 

It’s important to replace any highly processed foods and/or ones with unwanted additives, etc. with whole, minimally processed foods. This also includes adding back in essential components for proper digestion and absorption of food such as hydrochloric acid (HCL), digestive enzymes, and biles acids through supplementation. 

Step 3: Reinoculate

It’s crucial to restore beneficial bacteria in the gut to create a healthy balance of good bacteria to promote optimal function and maintenance of the tight junctions in the gut. This can be done through the combination of prebiotic and probiotic foods and/or supplements.

Step 4: Repair

To repair your gut, it’s important to provide your body with nutrients that will support this process such as vitamin D and zinc. Plus supplemental butyrate and L-glutamine have also shown beneficial effects on improving the health and function of the gut barrier and tight junctions.[11][12]

In addition to this, certain herbs are commonly used to repair the gut such as calendula, plantain, marshmallow root, and slippery elm. As well as herbal supplements like deglycyrrhizinated licorice (DGL) and curcumin. 

Conclusion

When it comes to understanding the connection between increased intestinal permeability and depression, research is still in its early stages. However as time goes on, we will likely uncover more evidence connecting the two and learn more about what is leading to leaky gut in the first place in individuals with depression. Knowing this can further help us understand how to best approach sealing up a leaky gut and ultimately reverse depression.

REFERENCES

. Kelly JR, Kennedy PJ, Cryan JF, Dinan TG, Clarke G, Hyland NP. Breaking down the barriers: the gut microbiome, intestinal permeability and stress-related psychiatric disorders. Front Cell Neurosci. 2015;9:392. Published 2015 Oct 14. doi:10.3389/fncel.2015.00392

2. Slyepchenko A, Maes M, Jacka FN, et al. Gut Microbiota, Bacterial Translocation, and Interactions with Diet: Pathophysiological Links between Major Depressive Disorder and Non-Communicable Medical Comorbidities. Psychother Psychosom. 2017;86(1):31-46. doi:10.1159/000448957

3. Obrenovich MEM. Leaky Gut, Leaky Brain?. Microorganisms. 2018;6(4):107. Published 2018 Oct 18. doi:10.3390/microorganisms6040107

4. Camilleri M. Leaky gut: mechanisms, measurement and clinical implications in humans. Gut. 2019;68(8):1516-1526. doi:10.1136/gutjnl-2019-318427

5. Thaiss CA, Levy M, Grosheva I, et al. Hyperglycemia drives intestinal barrier dysfunction and risk for enteric infection. Science. 2018;359(6382):1376-1383. doi:10.1126/science.aar3318

6. Vanuytsel T, van Wanrooy S, Vanheel H, et al. Psychological stress and corticotropin-releasing hormone increase intestinal permeability in humans by a mast cell-dependent mechanism. Gut. 2014;63(8):1293-1299. doi:10.1136/gutjnl-2013-305690

7. Summa KC, Voigt RM, Forsyth CB, et al. Disruption of the Circadian Clock in Mice Increases Intestinal Permeability and Promotes Alcohol-Induced Hepatic Pathology and Inflammation. PLoS One. 2013;8(6):e67102. Published 2013 Jun 18. doi:10.1371/journal.pone.0067102

8. Yamamoto EA, Jørgensen TN. Relationships Between Vitamin D, Gut Microbiome, and Systemic Autoimmunity. Front Immunol. 2020;10:3141. Published 2020 Jan 21. doi:10.3389/fimmu.2019.03141

9. Slyepchenko A, Maes M, Jacka FN, et al. Gut Microbiota, Bacterial Translocation, and Interactions with Diet: Pathophysiological Links between Major Depressive Disorder and Non-Communicable Medical Comorbidities. Psychother Psychosom. 2017;86(1):31-46. doi:10.1159/000448957

10. Ohlsson L, Gustafsson A, Lavant E, et al. Leaky gut biomarkers in depression and suicidal behavior [published correction appears in Acta Psychiatr Scand. 2020 Nov;142(5):423]. Acta Psychiatr Scand. 2019;139(2):185-193. doi:10.1111/acps.12978

11. Michielan A, D’Incà R. Intestinal Permeability in Inflammatory Bowel Disease: Pathogenesis, Clinical Evaluation, and Therapy of Leaky Gut. Mediators Inflamm. 2015;2015:628157. doi:10.1155/2015/628157

12. Wang B, Wu G, Zhou Z, et al. Glutamine and intestinal barrier function. Amino Acids. 2015;47(10):2143-2154. doi:10.1007/s00726-014-1773-4