The Connection Between Stress and the Gut Microbiome

Stress can significantly impact the health of the skin and has a well-known association with acne flares,^[1] atopic dermatitis,^[2] and even psoriasis.^[3] Psychodermatology is an emerging area within the field of dermatology, which addresses the effects of a person’s emotional stressors and mental health on the health of the skin.^[4] The normal stress response involves a cascade of hormones, particularly a hormone called cortisol, in response to danger or challenging circumstances. However, excessive or chronic stress can have undesirable effects on the skin. Researchers are beginning to learn more about an important link between gut health and skin health, and how stress can play a prominent role in this connection.

The gut microbiome, made of trillions of microorganisms along with chemicals they produce, is vital to our overall health. These microbial communities ideally live in harmony with one another, helping to provide us with vitamins, assisting in digestion, and regulating immune functions. Alterations, or unwanted changes, in the gut microbiome have been associated with obesity, diabetes mellitus type 2, and inflammatory bowel disease (IBD),^[5] and may even be an important determinant of skin health. There is a well-established connection between the gut microbiome and the brain, commonly referred to as the “brain-gut axis.” Stress-induced alterations in the gut microbiome may be one explanation for why you always seem to get a breakout during stressful events or in other demanding circumstances.

Does Stress Alter the Gut Microbiome?

The communities of microorganisms in the gut are constantly changing and fluctuating in response to lifestyle factors, such as diet, medications, illness, and stress. The gut contains a rich network of different types of nerves, and these nerves act like a two-way street between the gastrointestinal tract and the central nervous system. Disruptions in this nerve signaling tract are associated with eating disorders, gut inflammation, and chronic abdominal pain.^[6] In a mouse research study, mice that were subjected to 10 day periods of stress (by placing them in the vicinity of a more aggressive mouse) had a significantly less diverse gut microbiome and altered immune responses compared to the control group. This suggests a link between stress and disturbances in the gut microbiome;^[7] human studies are needed to see if the same features found in mice hold true in humans. Although still a new field of investigation, there is growing evidence that the composition of the gut microbiome is associated with nervous system function and is likely linked to mood disorders, such as depression and anxiety.^[7] Stress can increase the permeability of the intestinal lining, allowing gut bacteria to cross the intestinal barrier and activate an immune response. There appears to be a direct relationship between our stress and the health and diversity of our gut microbiome, which will be revealed further as research expands. 

There is a well-established association between stress and worsening of skin diseases, and although the exact mechanisms are not clear, the link between emotional stress and the diversity and function of our gut microbiome appears true. Incorporating stress reduction techniques, such as exercise and meditation, can help improve mental health to possibly improve the health of our gut microbiome as well as improve skin health.

Do Probiotics Reduce Stress?

Probiotics are live microorganisms that are widely available in capsule form, in beverages such as Kombucha, and in many other fermented foods such as yogurt. In addition, probiotics can be found in topical formulations, including personal care products. When taken in adequate doses, probiotics are known to confer health benefits.^[8] In fact, the use of probiotics may even reduce stress and alleviate skin conditions. According to one study, mice that received topical probiotics had improvement in stress-induced decline in hair growth.^[9] Researchers have hypothesized that probiotic supplementation may decease the stress-induced formation of damaging free radicals and could alleviate inflammatory skin diseases like acne and rosacea.^[10]

Stress appears to play an important role in skin health, likely by affecting the communication between the gut microbiome and the skin. However, our current understanding is based on mice studies and human studies are needed. Taking measures to reduce stress and keep your gut microbiome healthy, such as by taking a probiotic supplement, may have beneficial effects on skin health. Further research will help us continue to learn how stress affects the microbiome.

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