The age-old adage "you are what you eat" holds a profound truth, especially when it comes to the health of your skin. That is, while the digestive system plays a pivotal role in nutrient absorption and immune function, emerging research suggests a direct link between gut health and skin health. You read that right–the bacteria in your gut microbiome actually affect the condition of your skin.
Research studies on the gut-skin axis
You may have heard of the gut-brain axis, but the gut is actually connected to almost every function in your body, including your skin. The gut-skin axis refers to the bidirectional communication between your gut microbiome and your skin, i.e. the interplay between the bacteria in your gut, immune responses, and skin health. Research suggests that imbalances in the gut microbiota could contribute to skin disorders such as acne, eczema, and psoriasis. These conditions often involve inflammation, which is closely linked to the gut's immune response.
Specific bacteria impacting skin health
So which bacterial microbes impact skin health, and how? Here’s a list of just a few studied interactions…
Certain bacteria in your gut, like Faecalibacterium prausnitzii, Akkermansia muciniphila, and Ruminoccocus, can help protect against skin conditions like psoriasis. They do this by preventing harmful bacteria from taking over the skin and producing certain substances.
Helicobacter pylori, another type of bacteria, can contribute to signs of rosacea. It does this by producing toxins and causing inflammation in the gut, which affects the skin's processes, leading to redness, swelling, and changes in the immune system.
Faecalibacterium prausnitzii, when not in the right balance, can worsen chronic skin conditions like atopic dermatitis by causing inflammation in the gut.
Lactobacillus casei helps reduce inflammation in the skin by affecting specific immune cells.
Lactobacillus paracasei can shrink acne lesions and reduce inflammation by inhibiting certain processes in the skin.
Bifidobacterium animalis lactis helps alleviate itching in conditions like atopic dermatitis by changing the levels of certain substances in the body.
Bacteroides thetaiotaomicron has anti-inflammatory effects, which can relieve symptoms in conditions like atopic dermatitis and Crohn's disease.
Certain types of bacteria, like Clostridium difficile and Escherichia coli, when imbalanced, can contribute to the onset of atopic dermatitis in childhood by affecting the immune system.
Changes in the types of bacteria in your gut, such as a decrease in Firmicutes and an increase in Bacteroides, can lead to the development of acne by promoting inflammation.
Metabolites produced by these bacteria can also influence the skin. For example, short-chain fatty acids (SCFAs) can improve the skin's barrier and reduce inflammation.
Other substances like GABA, tryptophan, dopamine, serotonin, acetylcholine, phenol, p-cresol, propionic acid, sodium butyrate, galactooligosaccharides, fructooligosaccharides, polysaccharide A, retinoic acid, saturated fats, higher glycemic load, high peptides, and unsaturated omega-3 fatty acids play various roles in skin health, influencing factors like itching, inflammation, pigmentation, barrier function, and hydration.
Practical implications for gut-skin health
So now that it’s clear that gut health impacts skin health, what should you do with the information? Here are a few tips to maintain a healthy gut for radiant skin…
Probiotics and prebiotics
Incorporating probiotics, which are beneficial bacteria, and prebiotics, which are substances that promote the growth of beneficial microbes, into your diet can help maintain a healthy gut microbiota. Fermented foods such as yogurt, kefir, sauerkraut, and kimchi are excellent sources of probiotics, while prebiotics can be found in foods like garlic, onions, bananas, and asparagus. Or course, you can also take a probiotic supplement in addition to eating healthy foods.
Consuming a diet rich in fiber supports the growth of diverse bacteria in the gut. Whole grains, fruits, vegetables, and legumes are excellent sources of dietary fiber that can contribute to a balanced gut microbiota. There is also evidence that consuming fiber can improve skin wound healing and may help atopic dermatitis.
Of course, water is an obvious go-to for skin health (and overall health!), yet most people don’t drink nearly enough. Experts recommend 15.5 cups a day for men, and 11.5 cups a day for women. Drinking an adequate amount of water is crucial for skin hydration. Proper hydration supports the skin's ability to maintain its elasticity and suppleness.
Reducing sugar and processed foods
Another seemingly obvious solution for both skin and gut health has to do with sugar consumption. High intake of sugar and processed foods has been linked to disruptions in gut health. These foods can promote the growth of harmful bacteria and contribute to inflammation, negatively impacting the skin. Some studies suggest that sugar contributes to premature aging and skin conditions such as psoriasis and acne.
In summary, beauty (and health!) goes way beyond skin deep–it goes gut deep. The balance of bacteria in your gut and the substances they produce can impact your skin's health, either protecting against or contributing to various skin conditions. So if you’re looking to glow, go with your gut.