Skin, Autoimmunity, and the Gut

Many patients have skin conditions that can be traced back to inflammation and immunodeficiency that may have originated in the gut. Food allergies and sensitivities can express themselves as dermatological conditions, and because food sensitivities may go untraced for years without testing, damage to the lining of the intestinal wall can occur which not only creates inflammation in the gut, but inflammation in other organs of the body- including the skin.

Patients may think of the skin as merely the outer covering for their body, but the skin is an organ in its own right. In fact, the skin is the largest organ of the human body. It is not only a shield between a person and the world, but it also:

Actively helps protect us from the environment, bacteria, viruses, and fungi

Helps us to retain water

Acts to help regulate temperature in the body, including through sweating

Helps us navigate our environment and protect us from danger through nerve endings that give us our sense of touch and sense heat.

Is part of our immune system. Langerhans cells in the skin are part of the body’s immune system to help fight infections.

The skin also constantly renews itself, making new skin cells, and replacing the old ones. If the skin is healthy, not only do you look better, but you function better as well. 

Let’s look a little deeper at the gut-skin connection. When you eat foods that you are allergic or sensitive to, one of the early reactions you can see is the effect on the skin. Food allergies, which are IgE immune reactions, mean that the body sees the food (or other allergen) as an invader and attacks it. This attack is immediate and can be intense, and the results of the attack are typically seen within 15 minutes. For intense reactions, your throat may swell, making it difficult to breathe. You could lose consciousness and even die. Reactions of this intensity are somewhat rare, and most patients who are susceptible to these extreme allergies likely already know to avoid the foods or other allergens that trigger them. Less intense allergic reactions may affect the skin by causing hives, a rash, or even just mottled red patchiness. These reactions are also quite noticeable and the immediate symptoms fade relatively quickly. Again, a patient is likely to quickly link the food to this type of reaction and avoid that food in the future. Other allergic reactions may be more subtle, and harder to trace- you may flush, or feel slightly upset in the stomach, but perhaps not enough to think of a food reaction. Or perhaps a food allergy is considered but the offending food can’t be pinpointed through observation alone.

Another type of immune response is an IgG response. This sort of reaction to a food is not an allergy but is described as a food sensitivity. The immune system is still reacting to the food but with different immune players. These sorts of reactions take much longer to manifest- typically up to 72 hours after food has been consumed. This makes it even harder to trace which foods may be causing the reactions. What’s more, food sensitivities may have entirely different symptoms than food allergies do. Aside from the reaction not being immediate, they are unlikely to cause problems with breathing, or immediate skin conditions like hives, and they don’t release the same rush of histamines that can make someone feel warm all over. That doesn’t mean they aren’t causing a reaction, but the symptoms triggered can be completely different, including fatigue, brain fog, memory recall issues, intestinal cramping or diarrhea, or skin conditions like rashes, longer-lasting redness, skin sloughing or scabbing. Because food sensitivities and less noticeable food allergies may not be linked to food at all, or at least not a particular food, without testing they may persist in a patient for years.

That’s a problem for the gut and skin. The longer that food allergies and sensitivities persist, the more potential they have for damaging the gut through inflammation. That inflammation can not only damage the gut, sometimes permanently, but inflammation is at the root of many skin conditions. Unless you have contact dermatitis, where a substance that comes in direct contact with the skin is causing a skin condition, then the root of your skin condition is almost certainly an inflammatory response that arises from somewhere else in the body- and the gut is the usual culprit. Even before your gut becomes damaged, the inflammatory response that begins there from food allergies and sensitivities can cause skin rashes, redness, swelling, and a sensation of warmth in the skin.

Chronic inflammation in the gut can cause eczema. Eczema, also known as atopic dermatitis, is indeed a disease of inflammation. When a patient has eczema, their skin becomes inflamed, red, and itchy. With eczema, the immune system overreacts resulting in a state of constant, or chronic inflammation. Over time, this inflammation damages the skin, leaving it red and itchy. Since eczema is an atopic disease, this means the inflammation is coming from elsewhere in the body- usually, the gut, although activities like cigarette smoking can also cause a reaction by inflaming other organs, as can environmental allergens. Aside from diet, the other common triggers for eczema are chemicals and fragrances in detergents, cosmetics, and household cleaners, dust mites, pollen, pet dander, nickel or other metals, and certain foods. In the gut, food allergens and sensitivities are often the triggers for developing eczema, and they continue to drive the disease as the inflammation in the gut gets worse. Once that process starts, gut inflammation can also become more easily driven by eating foods that are highly processed or are high in histamines, or both. Certain foods increase inflammation in the body, including fried foods, sodas and other sugary drinks, red and processed meat, refined carbs like cookies, white bread, and cake, margarine, shortening, and lard. 

Patients who have eczema not only have these initial skin problems, but they also risk damaging their skin further. Constant scratching at itchy skin risks lichenification (thickening of the skin), which not only is cosmetically challenging but damages the integrity of the skin. That same scratching risks breaking the skin and causing infection, including staph infections, and herpes of the skin. Changes in skin color, trouble sleeping because of the itching, and permanent scarring can all be the results of long-term eczema. Understandably, these impacts on a person’s skin can also impact them psychologically. The National Eczema Association lists the following impacts on psychological health for those who have eczema:

1. Depression and Anxiety: Adults with eczema have a two-and-a-half to three-fold higher risk for anxiety or depression.
2. Suicidal Ideation: People with eczema are up to 44% more likely to exhibit suicidal ideation, and 36% more likely to attempt suicide.
3. Stress and Anxiety: The unpredictability of eczema flares and the limited ability of currently available treatments to effectively alleviate itch and afford long-term disease control correlates with symptoms of anxiety and/or depression.

Eczema can take a toll, and patients can be baffled as to why it’s happening to them. Testing for food allergies and sensitivities, and for environmental allergies is a good place to start.

Aside from general skin conditions and eczema, another skin condition that can develop because of gut disturbance and dysbiosis in the microbiome is psoriasis. Psoriasis is an autoimmune condition. This means that like eczema, the root of the inflammation is systemic, and it is an immunological disorder. Systemic inflammation can progress to autoimmune disorders if that inflammation becomes pervasive and chronic. The difference between other immune reactions and autoimmune conditions is that rather than the immune system misidentifying a food, for instance, as an immunological threat and attacking it, this has happened so many times that the immune system has become confused, and now attacks the cells of the body itself. We are discovering that many, and perhaps most or even all autoimmune conditions arise in the gut. When the tight junctions between the cells in the intestinal wall are weakened from inflammation in the gut (often resulting from food sensitivities) it allows inflammation in the gut to spread to other areas of the body. An effect on the skin can be Psoriasis.

Inflammatory skin conditions like psoriasis and psoriatic arthritis develop when the immune system triggers inflammation that attacks skin cells. 

Chronic inflammation, on the other hand, can manifest as fatigue, muscle aches, joint pain, gastrointestinal issues, weight gain, headaches, and skin rashes. 

Chronic inflammation can persist for months or years and is a contributing factor to more than half of deaths worldwide. 

Aside from the impact on the skin itself (and nails), and the accompanying psychological effects, one of the risks of psoriasis is that it may progress to psoriatic arthritis, where the immune system attacks the joints. This condition is not only painful and potentially debilitating, but it can express itself in other ways as well, including:

1. PsA causes inflammation in joints and tendons, leading to stiffness, swelling, and pain. Your fingers and toes may swell, developing a sausage-like appearance. This is called dactylitis.
2. PsA that affects your spine is called axial PsA. It may cause inflammation and bone growth in various parts of your spine that affect your back, shoulders, and hips.
3. PsA is associated with an increased risk of heart disease, strokes, and fatty liver disease.

So what is to be done for a patient to avoid going down the path toward these skin diseases and a possible autoimmune condition?  The very first thing should be a gut workup combined with a physical examination to assess for skin conditions and to identify what type may be affecting them. Precision Point Diagnostics offers comprehensive gut testing, including several stool tests, the Advanced Intestinal Barrier Assessment to evaluate leaky gut, and the G-DAP – Gut & Detox Assessment Profile to assess gut and systemic inflammation. Of course, an assessment of food allergies and sensitivities with the P88 Dietary Antigen Test, and environmental allergies with the Precision Airborne Allergy Test is also recommended to assess the root cause of gut and skin inflammation.