March 19, 2023

Our skin: Mirror of the soul. Mirror of the body.

The importance of the gut microbiome for our skin

Our skin: Mirror of the soul. Mirror of the body.

It gets under my skin

The language alone shows how important our skin is, for example when we “save one's own skin”, we react “thin-skinned” or “jump out of one’s skin”. In addition to describing our emotions, our skin also says a lot about our body and our state of health: Dry skin, brittle nails, hair loss, for example, can indicate a thyroid disorder (1, 2).

Drawn by life our skin reflects ...

• age and genetics
• lifestyle (diet, exercise, sleep, stress, cigarette and alcohol consumption)
• health status (diseases & medications) and
• living conditions (living & working situation, weather & environmental influences, personal experiences) (3, 4).

Marvel skin

With its 3 layers, our skin is the largest (1.5-2m2), heaviest (up to 10kg) and most versatile organ. It accommodates 6 million cells in just one cm2 and combines protection, permeability and elasticity in one. Our skin contributes significantly to our appearance and provides information on health and our current condition (swelling, reddening, paleness, yellowing, laugh lines, goosebumps, blushing, wrinkles on the forehead, etc.). Cosmetic features such as freckles, birthmarks, liver spots, but also tattoos or scars make our skin unique and thus also our personal characteristic (2, 4, 5, 6).


Our skin renews itself regularly and fulfills numerous functions in parallel: It forms a barrier, protects us from harmful environmental influences and dehydration, is of great importance for our metabolism, regulates our sensitivity to heat and cold, lets us perceive touch, pain and pressure, plays a major role in the immune system and is crucial for wound healing.

Besides stress our skin reacts to hormones, an unbalanced diet, climate changes and too little sleep as sensitively as its field of action is diverse. Just like our gut (2, 3, 4, 7)!

Gut & skin

Skin and intestines flow into one another. Both act as a barrier, protecting us from potential pathogens and harboring a microbiome of bacteria, fungi and viruses on their surface. They are connected to the endocrine system, have numerous vessels and nerves and are in constant contact (gut-skin axis). Accordingly, they react to disturbances in the other microbiome (2, 3, 7).

The development of inflammatory skin diseases (rosacea, neurodermatitis, acne) is promoted, for example, by dysbiosis (disorder of the intestinal microbiome). If vitamins, mineral nutrients and micronutrients important for the skin can no longer be optimally absorbed or toxic components pass through the intestinal barrier due to leaky gut (permeable intestine), inflammation or misdirected immune reactions can be triggered. If the immune system (70-80% of the immune cells are in our gut) is permanently overloaded due to an imbalance in the intestinal microbiome, chronic inflammation occurs, which can manifest itself in skin irritation, among other things (3, 5, 7, 8).

Influence of hormones

Stress and the excessive release of stress hormones not only affect the gut, but also the skin, hair and nails (2, 9, 10). Who doesn't know that moment when we see pimples or reddening in the mirror or when one "bad hair day" follows the next? Exactly when a particularly important meeting is coming up or the last few weeks have been intense and particularly challenging.

Changes in the skin's appearance depending on the monthly cycle - this is also well known to many. And here, too, the gut and its microbiome play a decisive role, namely in the regulation of estrogen levels. There is even talk of the «estroboloma». This is a collection of gut bacteria that can metabolize and modulate estrogen circulating in the body through the production of ß-glucuronidase. Both estrogen dominance and low estrogen levels are associated with unpleasant symptoms and illnesses and affect, among other things, the appearance of our skin (2, 4, 11).

Slept badly? Not only do we feel low on energy, our skin looks the same. The intestinal microbiome is also involved here: Serotonin(“happiness hormone”), as a precursor to Melatonin (“sleep hormone”), is 90% produced in our gut. An imbalance in the gut not only affects mood and sleep quality, but also the appearance of our skin (10, 12).

Apart from the fact that skin irritations are very unpleasant and can also indicate other diseases, the mental stress is often enormous (2, 13). The resulting emotional stress creates a negative spiral between the gut and the skin (9, 10).

5 practical tips to support the gut-skin axis:

anti-inflammatory effects of turmeric and ginger
• Ω-3 fatty acids in fatty fish, avocados or nuts
• olive, rapeseed or linseed oil instead of sunflower oil
• much water
• freshly prepared food instead of fast food and highly processed foods

In general, our skin likes ...

…. fresh, balanced, vitamin-rich diet with plenty of water, little alcohol and no nicotine. Exercise in the fresh air is very healthy for our skin, but without exposing oneself to extreme weather conditions (direct sun, cold, wind) or protecting oneself accordingly. Restful sleep is just as important for glowing skin as relaxation exercises and effective stress management (3, 14).

A balanced intestinal microbiome is supported in its functionality by all these measures and in turn helps the skin to be able to fulfill all its tasks and be clear at the same time.

Taking concrete action is easier when you know the microbial composition of your gut.

Interested in how diverse your gut microbiome is and how you can improve it?

Get in touch!


(1)    Joshua D. Safer (2011): Thyroid hormone action on skin, in: Dermato-Endocrinology 3(3):211-215.
(2)    Viktor A. Czaika et al. (2021): Kurzlehrbuch Dermatologie, 3. Auflage, Thieme Verlag, Stuttgart.
(3)    Iman Salem et al. (2018): The Gut Microbiome as a Major Regulator of the Gut-Skin Axis, in: Frontiers in Microbiology, 9: 1459.
(4)    Lorna Jeng, Anjaly Mirchandani (2021): Chapter 20 – Skin health: what damages and ages skin? Evidence-based interventions to maintain healthy skin, in: Emma Short: A Prescription for Healthy Living, Academic Press, 2021, 225-233.
(5)    Zohra Zaidi, Sean W. Lanigan (2010): Skin Structure and Function, in: Dermatology in Clinical Practice. Springer, London.
(6)    Rayhan Mahmud et al. (2022): Impact of gut microbiome on skin health: gut-skin axis observed through the lenses of therapeutics and skin diseases, in: Gut Microbes, 14:1.
(7)    Alok Malaviya et al. (2022): Gut-Skin Axis: Role in Health and Disease, in: Kavita Beri et al.: Probiotic Research in Therapeutics. Volume 3: Probiotics and Gut Skin Axis – Inside Out and Outside in. Springer, Singapore.
(8)    Britta De Pessemier et al. (2021): Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions, in: Microorganisms 2021, 9(2):353.
(9)    Nives Pondeljak, Liborija Lugović-Mihić (2020): Stress-induced Interaction of Skin Immune Cells, Hormones, and Neurotransmitter, in: Clinical Therapeutics, 42(5):757-770.
(10)  Thierry Passeron et al. (2020): Clinical and biological impact of the exposome on the skin, in: Journal of the European Acacdemy of Dermatology & Venerology 34(4):4-25.
(11)   Edwin D. Lephart, Frederick Naftolin (2022): Estrogen Action and Gut Microbiome Metabolism in Dermal Health, in: Dermatology and Therapy, 12:1535-1550.
(12)  Robert P. Smith et al. (2019): Gut microbiome diversity is associated with sleep physiology in humans, in: PLoS One 14(10).
(13)  Ari Tuckman (2017): The Potential Psychological Impact of Skin Conditions, in: Dermatology and Therapy 7:53-57.
(14)  Anne Gürtler et al. (2022): The impact of clinical nutrition on inflammatory skin diseases, in: Journal der Deutschen Dermatologischen Gesellschaft, 20(2):185-202.