The Gut-Skin, The Inside-Out Connection: How to Glow From Inside


The first line of defense we have to protect ourselves against oxidative damage that causes premature aging and inflammation is our skin!  It’s the largest organ we have and is strong and protective, yet at the same time can be very delicate. Crucial to its ability to fight off damage is a protective barrier called the acid mantle that has a mildly acidic pH level. It’s necessary to be slightly acidic in order to be an effective defense against harmful invaders but can easily disrupt the delicate balance of this barrier if we use poor quality creams and treatments on our skin. Many times we use these products trying to fix a problem but, in reality, are only making it worse.

The actual number of bacteria that reside on our skin and in our guts are countless and are an integral part of maintaining the health and quality of our skin.   The gut microbiome is what we call the microorganisms that live in our GI systems and the skin microbiome is what we call the bugs that live on our skin.  We are a living ecosystem and have to consider how we take care of our ‘bugs’ as well as ourselves because the microbiota living with us outnumber human cells 10 to 1! Some of the bacteria we have in our gut are good (such as lactobacillus and bifidobacteria), and some not so good (harmful bacteria, parasites, or an overgrowth of yeast known as candida).  It’s extremely important to have the right balance of good vs bad bugs in order to have a healthy, well functioning digestive tract, but many things can influence this balance including exposure to environmental toxins like pesticides, certain medications and the quality of our diets. What we eat is essential to having a healthy microbiome because this determines whether we are nourishing the good or the bad bugs in our gut.

The Inside-Out Connection

Many conventional doctors today still believe that what we eat doesn’t have any bearing on the health of our skin, but in fact recent research suggests that what we eat really does affect the quality of our skin.  One study done in 2014 published in the Journal of Drugs in Dermatology, suggests that eating foods high in refined carbohydrates and sugar plays a big role in the development of acne. Another study published in Journal of the American Academy of Dermatology in 2008 concluded that skim milk may contribute to acne!

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While there certainly are foods that can negatively impact the health of our skin, there are also a vast array of foods and nutrients that nourish us from the inside out.  In a more recent study published in the international journal Acta Dermato-Venereologica in 2014, research suggests how important it is to eat foods that contain an abundance of healthy fats like omega-3 found in fish oil, and gamma linolenic acids (GLAs). These fats help reduce inflammation and acne breakouts, actually doing the opposite of what skim milk does!

So how do we build the right balance of friendly bacteria in our gut?  There are several ways, but one of the most important is exposure to our mother’s own bacteria during a natural vaginal birth.  The bugs we get from our mother give us a good start for developing a healthy microbiome, but as we get older we’re exposed to an increased amount of toxins, stress, infections, medication, and a poor diet (the typical Standard American Diet or SAD). All of this combined has a negative impact on our microbiome, which can lead to inflammation – the underlying cause of many conditions and illnesses today including obesity and cancer.

Another way to get the good bacteria is by getting them from the food we eat. Some ‘germs’ may have a bad reputation, but not all of them are bad for us! Some bacteria are actually good for us and help promote our overall health, including the quality of our skin.  These bugs are known as ‘probiotics’ and are found in certain foods like kimchi, sauerkraut, pickled produce, yogurt, and kefir.

Prebiotics are the foods that promote the growth of good bacteria in our gut and sources include dandelion greens, garlic, onions, leeks, and chicory. It’s important to get enough prebiotics on a daily basis in order to feed and nourish the probiotics but if your gut is already damaged, you may need to do more than just get your probiotics and prebiotics from food.  If you suffer from symptoms of GI distress (nausea, bloating, gassiness, heartburn, constipation, diarrhea), have more-intense chronic skin issues like cystic acne or psoriasis, or have taken a lot of antibiotics or oral steroids in the past, you may need additional support.  A high-quality probiotic supplement can help get your gut back on track and improve the balance of good vs bad bacteria.  If your GI issues continue to persist, it may be necessary to see a licensed naturopathic physician like myself, or a functional medicine doctor who can run tests that will help determine the health of your gut microbiome.

We can’t ignore the fact that the health of our skin is directly related to the health of our gut. When we have a healthy GI tract our bodies are better and more efficient at absorbing nutrients resulting in healthier, better looking skin!  A healthy microbiome protects us from the harmful microorganisms that can have negative effects on the health and appearance of our skin.  The fact is you must have a healthy, well-balanced gut microbiome if you want clear, glowing skin.

It is extremely important to maintain the balance of the gut microbiome, in particular, because the fact is our skin is an extension of our gut.  Even if you don’t have any symptoms of GI distress, chances are you may still have gut dysbiosis (microbiome imbalance), especially if you have chronic skin problems, like acne or eczema.  This is a red flag that the integrity of the skin’s microbiome is disrupted and needs attention.

While we need a healthy gut microbiome, we also need a healthy skin microbiome.  The bacteria we have on our skin is made of different, yet equally important microorganisms and can protect us from harmful disease causing bacteria like Propionibacterium acnes – a bug that can trigger the development of acne. The skin microbiome also helps to maintain the skin’s immune function and its natural lipid barrier.  This can prevent not only acne but other skin disorders like eczema, from developing and it helps to slow down the development of wrinkles and saggy skin.

Why you need a balanced and healthy skin microbiome

The microbiome of our skin is extremely important but very often overlooked. Our skin’s natural pH level is about 4 to 4.5. A pH level below 7 is considered acidic while a pH level above 7 is considered alkaline. Because our skin is mildly acidic it is able to stay healthy and hydrated. For a long time, it was believed that a balanced pH for skin was neutral – 6 to 7, but research now tells us the pH should be under 5 keeping it a mildly acidic environment which helps to keep the microbiome more balanced. An alkaline pH (around 8 to 9) will disrupt the balance, and many common skincare products we use every day, multiple times a day, including, cleansers, toners and serums, have a pH over 5.5. Using these products can disrupt the pH balance of the skin, causing dryness, and making it more prone to damage and premature aging. Believe it or not, even water can be too alkaline for your skin. but you can rebalance the pH of your skin to mildly acidic by using high quality skin care products after it’s exposed to water.

The formula of a skin care product help determine its pH level. You might think that a lot of synthetic ingredients have to be used to make it more acidic, but there are many natural ingredients that will reduce the pH, making it mildly acidic. For example, citric acid is naturally occurring in citrus fruits, but when added to skincare products will increase its acidity. Not all skin care products are made with acidity in mind, so it’s important to read the label carefully and look at the ingredients. Sometimes you may find the pH level is listed on the label but if not there, you can contact the manufacturer to get the level. The Spa Dr. skin care line embraces this science!

There are also certain oils you can put on your skin that will help promote a mildly acidic pH level, and also have other ‘good for you’ skin balancing effects.  Argan kernel is an example of an oil that helps restore resilience to the acid mantle (barrier) of the skin and also gives it a luminous glow and softness.  It adds moisture to the skin and protects against dryness.  And, argan oil won’t clog your pores and is anti-inflammatory, so it’s really good for oily and acne-prone skin types.

When you give it proper nutrition from eating a whole food, plant-focused diet, your body does a great job maintaining its internal pH level.  But as you have read, both the gut and skin microbiomes play a big role in your skin health, so when both are properly balanced, you can see the difference in clear, youthful-looking skin. If you struggle with chronic skin issues, especially if you’ve taken or used topical or oral antibiotics and steroids or, have stripped your skin with invasive procedures, the gut-skin connection is something you’ll likely want to address.

Dr. Trevor Cates was the first women licensed as a naturopathic doctor in the state of California and was appointed by former Governor Arnold Schwarzenegger to California’s Bureau of Naturopathic Medicine Advisory Council. Known as the “Spa Doctor,” Dr. Cates sees patients at world-renowned spas and in her Park City, Utah private practice with a focus on anti-aging, hormone balance and glowing skin. Find out more details on how to achieve glowing, radiant skin in her book Clean Skin From Within.

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