This post is under review and in the process of being rewritten.
Probiotics for Gut Health and Skin Issues
The link between a healthy diet and clear skin has long been established. In IgE-mediated food allergies, pruritus and urticaria are observed immediately after an allergen (such as peanut) is ingested, among other manifestations of allergy.
Many inflammatory skin conditions such as atopic dermatitis (eczema) are idiopathic. Although they are suspected to be affected by genetic dispositions, it has become clear that the microbiome has a role to play in the immune reaction.
Restoring normalcy to the gut lining may translate to the normality of the skin and epithelium. In this issue of restoration of balance, probiotics find their use.
The role of probiotics in eczema symptoms has undetermined findings, however continues to be researched.
What is Gut Health?
Gut health simply refers to the state of the micro-organisms that line the gastrointestinal tract. These ‘’good bacteria’’ are essential for optimal health and digestion. There are about 300-500 species of bacteria living inside the stomach and adhering to the lining of your mouth, throat, stomach and intestines.
These microbes prevent many diseases by simply occupying the space a pathogen needs to anchor itself and cause an infection. Also, these friendly bacteria release some enzymes that are essential to digestion in humans.
When the line of defence formed by these microbes is compromised, a gut illness can occur. This is seen in approximately 70 million Americans who suffer from gut health issues such as Leaky Gut.
An equilibrium if said to be required between the microbes and their environment to have a healthy gut. Too many or too few of these bacteria will cause digestive diseases.
What is the microbiome?
The microbiome is a community of organisms found in all body parts but most concentrated in the stomach and intestines. The gastrointestinal environment is harsh and highly acidic, which deters the growth of many kinds of bacteria. However, a host of organisms find these conditions suitable. Common microbes that make up the microbiome include Staphylococcus species, Streptococcus species, and Lactobacillus.
What do these organisms want?
The microbes in the gut are mostly symbiotic; their actions benefit them just as much as they help the human body. These organisms want food and shelter in return for the digestive aid and protection they offer most of the time. They feed on the food that enters the stomach and replicate at such high rates that no other microbe (pathogen or not) has any space to anchor itself. As they feed, they produce helpful enzymes that help accelerate digestion.
In a healthy individual, these microbes only take an insignificant amount out of your diet, hardly shortening your ration at all. When the stomach is emptied, replication immediately ceases. This manages the proliferation of the microbiome.
A few opportunistic pathogens are harmless until the immune system becomes compromised by infection or disease.
How do they help us?
The microbiome digests complex polysaccharides which are otherwise indigestible by humans. They are a metabolic aid, converting sugars into Vitamin K, B12, propionate and butyrate. These metabolites are essential in maintaining a healthy epithelium. (1)
The Link Between Gut Health, Skin issues (Eczema) and Immune system
The Gut-Skin axis fosters the relationship between the gut and skin. The exact mechanism of eczema is not known, but a combination of genetics, environment and gut health play a role in its pathophysiology. The stomach, duodenum and oesophagus act as reservoirs for IgE+B lineage cells. This is why food allergies translate to psoriasis and atopic dermatitis in predisposed individuals.
A derailment from the normal microbiome condition of the gut is called dysbiosis, and dysbiosis is a common cause of inflammatory skin diseases mediated by the immune system. About 7-11% of people with Irritable Bowel Disease (IBS) also suffer from a chronic case of psoriasis. (2)
The metabolites of the microbiome serve anti-inflammatory purposes. According to one study, butyrate, a short-chain fatty acid, suppresses the immune system by inhibiting inflammatory cells’ proliferation, migration, and adhesion. The study also claims that this metabolite can halt cytokine production. (3)
When the integrity of the gastrointestinal lining is compromised, the gut microbiome and its metabolites are spilt into circulation, which upsets the homeostatic balance. Gut microbiota tends to accumulate in the skin. Furthermore, another study states that the DNA of gut microbiota have been found in the plasma of patients with chronic psoriasis. (4) This proves the systemic involvement of gut microbiota in skin-related diseases.
More detailed studies are required to ascertain how the gut microbiome influences skin diseases.
What are probiotics?
Probiotics are dietary supplements that may repair the microbiome. A probiotic contains live organisms that, when ingested, occupy the gastrointestinal tract. The organisms commonly found in a probiotic are Saccharomyces boulardii, Lactobacillus and Bifidobacterium.
Probiotics may come as natural foods or as a supplement. Common foods that contain helpful intestinal microbes include yoghurt, buttermilk, miso, tempeh, kimchi and other fermented foods and spices.
Benefits of Probiotics
The mechanism through which probiotics influence oral health is similar to that of gut health. Probiotics, especially those containing Lactobacillus, have shown a significant effect on the development of periodontal diseases such as gingivitis, periodontitis and pregnancy periodontitis. (5) in this case, the microbes suppress the inflammatory action of normal saliva microbiota.
Probiotics may also prevent dental plaques and caries, a leading cause of halitosis and poor dental health. Research has revealed that probiotics can reduce the occurrence of plaques by inducing environmental pressure and competition. Unfortunately, benefits have only been seen in a small population. Studies are still being carried out on what probiotic organisms would have the most impact on plaques(5).
Lactic acid-forming probiotics such as Lactobacillus can assist in maintaining vaginal health. Lactobacillus makes up a more significant percentage of the vaginal microbiome, and its metabolites sustain the pH of the vaginal environment.
The competitive adherence of Lactobacillus to the epithelium of the vagina prevents infections that lead to bacterial vaginosis, vulvovaginal candidiasis and yeast vaginosis. (6)
The use of probiotics in preventing bacterial vaginosis is becoming increasingly popular, and investigations are being made into its effect on preterm deliveries. Many pre-term deliveries and neonatal mortality are caused by Chorioamnionitis, a complication of bacterial vaginosis. As such, the prevention of bacterial vaginosis through probiotics has been included in several antenatal care programs. (7)
Infections, allergies and cold
Probiotics certainly play a role in suppressing food allergies, although the extent of their effect is not certain. Probiotics made from Lactobacillus have shown significant improvements in cow milk allergies among specific populations(8).
Probiotics have also been proven to reduce the incidence and severity of colds among schoolchildren. According to one study, children who take probiotics are less susceptible to rhinoviruses, cough and fever (9). However, probiotics have no effects on nausea, vomiting and diarrhoea caused by allergies and colds.
The use of probiotics in children needs to be closely monitored due to the possibility of a rebound infection. Probiotics should be employed only when the benefits outweigh the risks.
Reduce side effects due to antibiotics
Probiotics can be used to augment and, in some cases, replace the use of antibiotics. The high incidence of side effects with antibiotics and the prevailing antimicrobial resistance has encouraged the search for alternatives to antibiotics.
The use of probiotics may reduce the need for antibiotics by supplementing epithelial lining integrity and immunity. Thus, antibiotics are reserved for when they are most needed. This may curb the steep resistance curve.
Further, many antibiotics are known to cause side effects such as diarrhoea and GI disturbances. Prebiotics may again play a role in mitigating these side effects, making antibiotics more bearable. (10)
Probiotics for the Immune System, Digestion, Eczema, Gut Health
Irritable Bowel syndrome
Probiotics can improve the symptoms of irritable bowel syndrome (IBS) by offsetting the balance between the pathogens and microbiota present in the stomach. The actions of probiotics in the management of IBS may be classified into physical barrier effect, competition and metabolic effects. Recent studies have revealed that probiotics may relieve pain associated with digestive abnormalities by inhibiting opioid and cannabinoid pain receptors in the gastrointestinal epithelium. (11)
Probiotics also regulate intestinal inflammatory responses by inhibiting cytokines. They act on Interleukins and dendritic cells, the antigen-presenting cells for T lymphocytes. These cells are related to the activation of B lymphocytes.
Reduced risk of colorectal cancer
Probiotics may be used in the prevention and management of colorectal cancers. Although the exact mechanism through which probiotics affect colorectal cancer remain unknown, many possibilities have been identified. A few of the postulated methods through which probiotics prevent colorectal cancer are the inactivation of carcinogenic compounds, competition with putrefactive pathogens, inhibition of tyrosine kinase pathways, regulation of apoptosis and cell differentiation. These discourage the proliferation of cancer cells in the colon and rectum. (12)
The intestinal microbiota binds to possible carcinogens found in food, especially those that occur due to digestion. The complexes formed between metabolites of microbiota and those of red meat reduce the exposure of the colon and rectum to mutagens.
Improved digestion in Lactose Intolerance
The intestinal microbiota consists of many Lactic-acid fermenters. In the lactose-intolerant population, a deficiency of the enzyme lactase prevents the proper digestion of Lactose, the sugar found in milk and milk products. This usually leads to abdominal pain and often diarrhoea.
Probiotics relieve the symptoms of lactose intolerance by hydrolysing lactose and precipitating colonic fermentation. Lactic acid bacteria produce a beta-galactosidase enzyme that performs the role of the human Lactase enzyme. The anti-lactose effects of probiotics begin in the small intestine and continue in the colon.
Treatment of skin conditions, psoriasis, eczema
Probiotics can be used to treat various skin conditions, its primary action being effected through the Gut-Skin Axis. The use of probiotics for the treatment of atopic dermatitis (eczema) has been confirmed safe and effective for children (13). However, more research must be done to ensure its effectiveness against eczema in adults.
In adults, probiotics have been used to treat and manage acne and psoriasis. Some studies say that probiotics reduce the risk of skin cancers to some extent, especially in otherwise predisposed individuals. (14)
Furthermore, probiotics show a promising role in encouraging wound healing (15)
Probiotics are known to influence the immune system. Recent studies show that probiotics have an effect on both adaptive and innate immunity. Probiotics affect the T and B lymphocytes of the adaptive immune system and the dendritic cells and macrophages of the innate system. (16)
According to the study, a mixture of probiotics induced both T and B lymphocyte hyporesponsiveness. This mixture also downregulated the T-helper cells without inducing apoptosis. These results may be helpful in the regulation of auto-immune diseases and hyperactive immune systems, which are often the cause of allergies and hypersensitivity reactions.
The particular dose at which the beneficial effects can be witnessed is not specific. Some studies vote in support of a lower amount than currently employed. In contrast, others say that a higher amount is necessary due to the anatomical differences between test organisms and humans. (17)
Beneficial and Common Probiotic Strains For Eczema
A proposed common cause of an eczema flare is the dominance of one particular species of bacteria in the gut. The more diverse the microbiome, the less prone an individual is to acne breakouts and flares. No two individuals have the same microbiome composition. However, the following strains and species have been known to have the most protective effects against eczema in humans.
- Lactobacillus rhamnosus
- Bifidobacterium lactis
- Lactobacillus acidophilus
- Lactobacillus paracasei, among others
Probiotics and Topical Steroid Withdrawal
With probiotics being used as a supplement to assist in improving the immune system, eczema, psoriasis, and wound healing, many people within TSW online communities and support groups consider improving their gut health with probiotics. As topical steroid withdrawal is a new phenomenon, we will update this page with relevant medical publications and evidence of the efficacy of probiotics and its relationship with topical steroid withdrawal. Anecdotally, we are seeing a strong trend of the usage of probiotics among people experiencing topical steroid withdrawal. It is important to note that there is no current medical cure for topical steroid withdrawal, however managing the underlying symptoms of eczema and inflammation can be mitigated.
The benefits of probiotics are not limited to skin and gut disorders. These living organisms offer a promising role in metabolic abnormalities such as obesity and the symptoms of type 2 diabetes. Further studies and research around probiotics may prove beneficial to the mental health of people living with conditions like depression and anxiety. Usage of probiotics to treat atopic dermatitis, eczema and psoriasis continues to grow and may be beneficial in managing the withdrawal period upon the discontinuation of topical steroids, however further medical research is required regarding this new iatrogenic phenomena.
- Huang B.L., Chandra S., Shih D.Q. Skin manifestations of inflammatory bowel disease. Front. Physiol. 2012;3:13. doi: 10.3389/fphys.2012.00013. [PMC free article] [PubMed] [CrossRef] [Google Scholar]