‘Gut-Skin Axis’ involvement in acne vulgaris
Did you know that there is a huge bidirectional connection between your gut and skin homeostasis?
The bacteria in your microbiome exerts many beneficial functions and produces by-products which interact with your immune, nervous system and endocrine pathways. A state of microbial imbalance in your gut (also known as dysbiosis) contributes to altered skin barrier integrity and increased epithelial permeability which results in pro-inflammatory cytokine production and chronic skin inflammation.
How does the Gut microflora communicate with the skin?
1. Absorbs skin loving nutrients (vitamin A, E, C, D) and minerals (Zinc and selenium)
2. Absorbs nutrients needed for correct hormone synthesis and detoxification which reduces unwanted circulating hormones that contribute to acne vulgaris (high cortisol, androgens and oestrogen)
3. The beneficial bacteria secrete short‐chain fatty acids (SCFAs) including butyrate, propionate, acetate and lactate from fibre fermentation. SCFA’s have been studied to promote skin barrier integrity and exert anti-inflammatory effects
4. Secrete antibacterial proteins which inhibits the growth of P.acnes (most dominant acne bacteria which live on the skin)
5. Beneficial bacteria have been studied to lower glycaemic load through their role in metabolism (intestinal incretin secretion, bile acid metabolism, and adipose tissue regulation). This decreases ‘Insulin-like growth factor-1’ signalling, involved in heightened sebaceous gland activity (pathophysiology of acne vulgaris)
How to achieve healthy skin from the inside – out
1. Reinoculate the microbiome with beneficial bacteria. Probiotic strains which have be researched to benefit the skin include;
- Lactobacillus brevis: reduces skin dehydration (transepidermal water loss)
- L. acidophilus and B.bifidum: exert anti-inflammatory effects in patients suffering acne vulgaris
- L. rhamnosus: normalizes skin expression of genes involved in insulin signalling (insulin like growth factor-1) which is involved in adult acne
- Saccromyces boularrdi: a preliminary study found more than 80% of those taking S. boulardii experienced considerable healing of acne in 5 months
2. Repairing the intestinal wall
- Collagen: full of amino acids needed to heal the damaged cells and re-build new tissue
- L-Glutamine: an amino acid studied to provide fuel for enterocytes (cells located on the intestinal wall needed for nutrient absorption and gut barrier function)
3. Eat a Balanced diet and remove aggravating dietary factors
- Protein: Amino acids are essential for collagen and keratin production which form the structure of skin. Anti-inflammatory protein sources include: salmon, trout, turkey, beans, lentils, tofu, sardines, anchovies and herring
- Omega-3 Fatty Acids: Reduces inflammatory markers, regulates hormones (especially testosterone) and decreases the rate in which the liver produces Insulin-like growth factor -1. Recommended EPA/DHA sources include: salmon, herring, tuna, sardines, Seaweed, nori, spirulina, and chlorella
- Prebiotics (fuel sources for the beneficial bacteria mentioned above): onion, garlic, green bananas, partially hydrolysed guar gum, Jerusalem artichoke, leeks, asparagus, barley, Konjac root and cocoa.

Resources
Girard-Pipau, F., Pompei, A., Nano, J. L., Boquet, X., & Rampal, P. (2002). Intestinal microflora, short chain and cellular fatty acids, influence of a probiotic Saccharomyces boulardii. Microbial ecology in health and disease, 14(4), 221-228.
Hechtman, L. (2012). Clinical Naturopathic Medicine (1st ed.).Chatswood, NSW: Elsevier Australia.
Ogawa, M., Saiki, A., Matsui, Y., Tsuchimoto, N., Nakakita, Y., Takata, Y., & Nakamura, T. (2016). Effects of oral intake of heat-killed Lactobacillus brevis SBC8803 (SBL88™) on dry skin conditions: A randomized, double-blind, placebo-controlled study. Experimental and therapeutic medicine, 12(6), 3863-3872.
O’Neill, C. A., Monteleone, G., McLaughlin, J. T., & Paus, R. (2016). The gut‐skin axis in health and disease: a paradigm with therapeutic implications. BioEssays, 38(11), 1167-1176.
Salem, I., Ramser, A., Isham, N., & Ghannoum, M. A. (2018). The gut microbiome as a major regulator of the gut-skin axis. Frontiers in microbiology, 9, 1459.