The Gut-Brain-Skin Connection

The Gut-Brain-Skin Connection

Apr 01, 2020

While the gut’s connections run deep, researchers have been investigating its link to skin since 1930. Since your brain and gut are in constant comms, together they decide how your digestive disturbances will surface on your skin. Though this may sound seamless enough, your skin has its own microbiome to deal with, also known as “skin-flora” Couple that up with environmental factors and you’ve got a wide arena open for a wild array of outcomes.

You are what you absorb

Your skin and your gut are the same, but different. Both protect you against harmful invaders, also coined “pathogens” and both are directly connected to your whole-body health. When healthy, both are covered in good bacteria, and whereas the gut contains 300-500 different species of bacteria, the skin houses nearly a thousand. As your body’s largest organ, the skin is also very porous and absorbent, and can soak up an average of 64% of whatever you put on it. That means the air you breathe, the water you drink, and of course, the food you eat.  

Gut health and skin conditions

Unwelcome visitors checking in on your chin? This is about much more than chance. While your skin’s health is closely tied to hormonal flux and hygiene, an unhealthy gut can often make an appearance on your skin. From spotting to sores, symptoms of a bacterial imbalance and inflammation can become seriously visible on your face. On one end of the spectrum of severity is Crohn's disease, an inflammatory bowel disease which can manifest in the skin through mouth sores and rashes. On the other hand, a recent study found those with rosacea are ten times more likely to have bacterial overgrowth in their small intestine than those without. Are you familiar with the adage “you are what you eat”? The saying also goes when it comes to skin health. Turns out, foods high in refined grains and sugars (like white rice, pasta, bread and desserts), as well as fast food and dairy products, can crop up in more undesirable places than one. Studies etch a bold line between what goes into your system and what flourishes on your face.

Stress, skin and gut health

Stress can have a chemical reaction on your skin that makes it more sensitive to the world around it. Initiating cortisol production, stress forces your glands into creating more oil, which eminently rushes to the surface of your skin to forge an inviting plane for pesky conditions like acne. Aside from this, it is also said that emotional states like stress can have a negative effect on the gut’s microflora, which can increase inflammation and intestinal permeability (also known as “leaky gut”), as well as contribute to whole body inflammation. 

Probiotics and skin conditions      

Makeup artists and facialists are increasingly investing in probiotic technology to help address the root issue: your gut. Much as 70-80% of your immune system is found in your gut; who would have thought it the complexion clairvoyant? While the science is still new, some studies have cited specific probiotic strains (namely Lactobacillus acidophilus, L. acidophilus, and B. bifudum), showing their potential to help reduce the appearance of acne and skin lesions over time. The good news is double-edged: first, you can find these strains in soy, tempeh and pickles, second, if you can’t: there’s always a supplement. 

Food sensitivities and skin conditions

Unlike food allergies and anaphylaxis, food sensitivities can be a lot more subtle and creep up slowly, going from glowing skin to dry, scaly, itchy eczema patches in days. The prevalence of food sensitivities is believed to be 5-20% of the general population, but the true prevalence is unknown due to lack of testing and data. This slow acting food intolerance is believed to be caused by increased gut permeability, or leaky gut, where there are small holes in the lining of the intestines allowing food substances to leak through and gain access to the circulation and trigger a food specific reaction on the skin. People will often experience gastrointestinal issues also, including stomach cramps, diarrhea, and constipation, suggestive of irritable bowel syndrome. Some other common symptoms include migraines, asthma, chronic fatigue and hair loss. Avoidance of the eating the foods that people were sensitive to resulted in significant improvement of skin and other symptoms. The most common food sensitivity reactions were to cola nut, brewer’s yeast, wheat, red kidney bean, pea, egg white, barley, pistachio, cow’s milk, and gliadin (a component of gluten).


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