There is a bidirectional link between the gut and the skin, and the health of each can affect both long term and short changes in the other. The functioning of your gut microbiome is intrinsically linked to the health of your skin and is one of the main regulators of the gut-skin axis including playing a key role in the regulation of epithelial cell turnover, repair of UV light exposure, skin hydration, controlling the speed of wound healing and influencing the microbiome of the skin.
We typically think of our gut microbiome as the population of good and bad bacteria that live in the mucosal barrier of our gut lining, but this population is more than just bacteria – it also includes viruses, fungi and protozoa (single cell organisms). Also the terms ‘good and bad’ are a little too simplistic; a healthy microbiome contains a diverse, balanced population.
Intestinal dysbiosis (disruption of the gut microbiome) influences the production of pro-inflammatory cytokines and cells that suppress the immune system. These cytokines increase the permeability of our skin’s barrier cells, creating chronic systemic inflammation that can be expressed as acne, dermatitis, eczema and psoriasis.
Additionally, the gut microbiome plays an important role in nutrient absorption. If nutrient absorption is impaired at the gut level then the repair and renewal of our skin cells with suffer as they will not be provided with sufficient amino acids, fatty acids and vitamins and minerals needed for collagen production, detoxification and protection of the phospholipid bilayer.
Prebiotics are a specific type of fibre (including short chain fatty acids) that feed and nourish the gut microbiome. We can take these as supplements, or include prebiotic fibre rich foods such as artichokes, apples, leafy greens, onions and garlic. in our diet.
Probiotics are bacteria and yeast that can help replace and increase the diversity of your gut microbiome. They can be taken in supplement form and found in fermented foods such as yoghurt, kefir, sauerkraut, kimchi and kombucha.
Postbiotics: postbiotics are metabolites that are produced when probiotics populate and ferment in the gut. These can include nutrients such as vitamins b and k, amino acids, short chain fatty acids and antimicrobial peptides that minimize the growth of unhealthy bacteria in the gut.
Healthy postbiotics include nutrients such as vitamins B and K, amino acids, and substances called antimicrobial peptides that help to slow down the growth of harmful bacteria. Other postbiotic substances called short-chain fatty acids help healthy bacteria flourish. Postbiotics are made naturally in the gut, but supplementation can be helpful in those with dysbiosis.
In short (!), pre, pro and postbiotics help maintain the health of the microbiome, which in turn helps the health of the skin via the mechanisms mentioned above.
What you don’t eat is just as important for a healthy gut as what you do eat – diets high in sugar and refined carbs can contribute to the growth of unhealthy bacteria and yeasts (such as candida), which can contribute to acne, breakouts and fungal infections of the skin. Highly processed foods and unhealthy fats can increase the intestinal permeability of the gut lining which in turn can slow down skin cell turnover and increase chronic, systemic inflammation.
In addition to including foods and supplements that contain pre, pro and post biotics, foods that help heal the intestinal lining can be incredibly beneficial to gut and skin health. By healing the intestinal lining you are providing a healthy environment in which the gut microbiome can flourish, minimizing inflammation by preventing undigested food particles, toxins and bacteria from entering the bloodstream and improving the absorption of nutrients (amino acids, antioxidants and phytochemicals) that are essential for skin health.
Specific amino acids have also been clinically improved to improve the health of the intestinal lining and therefore the gut microbiome and they include arginine, glycine, cysteine glutamate, and glutamine. These can be found in bone broth and collagen powders and supplements or can be supplemented individually for vegans. As an added benefit these amino acids also improve the skin’s collagen protection and production, so do double duty for skin health!
Yes, in a number of ways. These conditions are inflammatory in nature, and when inflammatory cytokines are increased at the gut level we also see this have a negative effect on inflammatory skin conditions and epithelial cell turnover and renewal. SIBO can increase the production of toxic metabolites, which can increase intestinal permeability and inflammation, and all of these conditions affect the absorption of nutrients for skin health which can lead to impaired skin cell renewal and a thin, dry and dull appearance.
A healthy diet that is low in sugar and processed foods, high in protein, healthy fats, fibre and antioxidants and phytonutrients is key for a healthy gut. In addition I recommend a targeted probiotic (one that contains a strain called Saccharomyces boulardii) that encourages a balanced microbiome, a liposomal vitamin C supplement and a minimum of 10g of collagen powder a day.