26 Feb 2018
If we look back just a couple of decades, many people had not even heard the term ‘probiotic’, but awareness of ‘friendly bacteria’ has been gradually increasing, mainly due to the increased amount of scientific research being conducted in this area. Some unexpected links between probiotics and a variety of different health conditions are being made, and one area where you might be surprised to find the words ‘probiotics’ and ‘live cultures’ cropping up is on the packaging of high-end cosmetics and skincare products.
Yes, there is now a huge interest in the potential benefits of probiotics for skin health. In fact, there are several brands of skincare using live cultures - or in some instances both pre- and probiotics - in their products. Marie Drago, the creator of Gallinee, a French skincare company that has launched five probiotic products to the market, explains that live cultures might help the skin retain its natural balance. Our skin should have an acidic pH, but this delicate pH balance is often disrupted by using harsh soaps and other chemical-laden cosmetics - Drago believes that by using their pre- and probiotic based cosmetics, balance can be restored to the skin.
Having been more used to finding our probiotics in the supplement aisles of ‘all good’ health food shops, you may wonder whether there is any sound scientific research to support the use of internal or topically applied probiotics for skin health. But according to Dr. Whitney Bowe, a New York-based dermatologist and clinician: "researchers are studying how healthy bacteria applied topically to the skin, or taken orally can benefit certain skin conditions".
So with regards to topically applied probiotics, Dr. Bowe mentions that they are thought to support skin health in a number of ways. Firstly, she says that they may act as a type of ‘shield’ or protective barrier, preventing pathogenic organisms from finding available binding sites on our skin cells. This prevents the triggering of an immune reaction and a subsequent localised inflammatory response in the skin, such as the type of response seen in rosacea and eczema for example. Secondly, her team is also investigating the theory that certain strains of probiotic bacteria can produce anti-microbial substances that help to limit the populations of pathogenic (or ‘bad’) bacteria on the skin. Work is underway to identify which probiotic strains offer the best anti-microbial activity, and it is hoped that this research may be useful in the future to develop targeted probiotic skin care products. Lastly, Dr. Rowe states that probiotics may have a ‘calming effect’ on the skin. By this, she means that probiotic bacteria prevent skin cells from sending ‘attack’ messages to the immune system and therefore prevent an over-active immune response, which could lead to skin inflammation.
When looking back over the scientific research, it appears that the notion that topically applied probiotics may be helpful in acne and other skin conditions is not actually as new as we might have thought. In fact, a clinical paper was published as long ago as 1912, showing anecdotal evidence that application of Lactobacillus bulgaricus to the skin offered positive effects in both acne and seborrhea. However, it was not until 1999 that proper scientific techniques were available to be used to accurately analyse what the potential benefits were and how they may occur.
In 2010, results of an in-vitro clinical trial1 were published in the European Journal of Dermatology. The study showed that the topical application of a certain strain of probiotic bacteria (Lactobacillus paracasei CNCM-I 2116) to skin cells that had been taken from human abdominal tissue, reduced inflammation, reduced oedema and also reduced atopic (meaning allergic) reactions in the skin cell culture. Additionally, researchers noted that barrier function was recovered significantly more quickly after disruption than it was in control samples that had not been exposed to the probiotic. In conclusion, the study author stated that the results of the trial ‘support a beneficial role of Lactobacillus paracasei CNCM-I 2116 on key biological processes associated with barrier function and skin reactivity.’
In 2009, a different study2, which was written up in the Journal of Microbiology, showed that a natural ‘antibiotic-like’ agent produced a strain of the bacteria Enterococcus faecalis SL-5 significantly reduced inflammatory lesions and ‘pustules’ when applied to the skin of patients suffering from acne vulgaris. This natural ‘antibiotic’, known as an enterocin, was concentrated and made into a powder that was added to a skin lotion, and used topically by acne vulgaris sufferers over an eight week period. Members of the probiotic group saw a reduction in inflammatory lesions of over 50% compared to the control group.
Skin conditions are typically characterised by two main skin anomalies: defective barrier function and/or inflammation. Whilst to date there have not been many clinical trials done on the topical use of probiotics for skin conditions, the few that have been completed do suggest that these two main physiological factors can be improved through the topical use of specific strains of bacteria.
So we've seen that probiotics applied topically may help to improve the health of your skin, but is it also worth taking them orally for this purpose? Again, this is an area that's interested scientists for decades, and physicians writing as long ago as the 1930s alluded to the popularity of drinking Lactobacillus acidophilus cultures in order to treat acne. However, it wasn’t until 1961 that a formal clinical case report3 was published by a physician in Baltimore, the U.S, who followed 300 patients treated with a mixture of L. acidophilus and L. bulgaricus. The probiotics were given for two intervention periods of 8 days each, with a two week ‘wash out’ period in between interventions. He reported that 80% of those with acne had some degree of improvement.
More recently, a study4 involving 56 patients with acne showed that the consumption of a fermented dairy beverage containing strains of probiotic Lactobacilli bacteria over a twelve week period significantly reduced total lesion count, and also markedly reduced sebum production in acne sufferers. It has also been proven in animal models5 that taking oral probiotics can reduce skin inflammation, or more specifically ‘antigen-specific skin inflammation’. This type of skin inflammation is seen in allergic skin diseases such as hives and eczema. When L. casei DN-114 001 was given to allergic mice it was seen to alleviate skin inflammation by regulating the release of molecules known as ‘inflammatory cytokines’ These are essentially messenger molecules of the immune system, that can either ‘switch on’ or ‘turn off’ inflammation in the body. Importantly scientists concluded that this anti-inflammatory effect was gained without causing any unwanted immune suppression. The authors of this animal study concluded by saying that ‘L. casei (DN-114 001) may thus represent a probiotic of potential interest for immunomodulation of allergic skin diseases in humans’.
Now that we're becoming more aware of the importance of maintaining a balance in our skin microflora, the potentially negative effects of products which may disturb this natural balance, in the same way as antibiotics disrupt our gut microbiome, are being scrutinised by scientists. Of course, where a prevalence of pathogens is suspected there may well be a place for such cleansing products, as there is for antibiotics when pathogenic infections occur in the body, but over-use of these bacteria-killing gels and washes is now not recommended. Our fear of all bacteria has resulted in an extensive array of hand sanitisers and antibacterial hand-washes being marketed over the past few years, but recently, the FDA in America banned a range of antibacterial ingredients6 such as triclosan and triclocarban as they have been shown to have negative effects and were no more effective at eradicating harmful bacteria than plain soap and water7. For more about why it may pay us not to be 'too clean', take a look at my blog about the 'hygiene hypothesis'.
It's believed that all of the resident bacteria in the body, whether they're located in the gut, skin, or elsewhere, play their part in the maintenance of good health, but with our modern lifestyle, we constantly disrupt the natural balance of these populations. A 2017 study8 said that "the human skin is home to a diverse and specific community of microorganisms, which include members that exist across the ecological spectrum from pathogen through commensal to mutualist. Most evidence suggests that the skin microbiota is likely of direct benefit to the host and only rarely exhibits pathogenicity".
But it appears that we can now use probiotics to restore the natural balance of our skin microflora and this, along with sensible hygiene practices which respect and maintain our tiny, invisible armies of beneficial bacteria, can help to keep the microbiota of our largest organ, the skin, in happy harmony.
It seems that our ancestors knew all about the power of probiotics, as there is a wealth of anecdotal evidence going back many decades supporting the use of live cultures for different skin conditions, but it's encouraging now that research is slowly being carried out which may validate and support these long-held beliefs. It appears that science is starting to catch up on what generations of ‘grannies’ and ‘old wives believed, that probiotics, whether applied topically or taken internally, may have a positive impact on skin health, and there may well be some truth in your granny's advice that putting natural yoghurt on your face helps you to stay young and beautiful! Modern research techniques are now able to identify the various mechanisms of action that probiotics utilise in order to improve the symptoms of many different skin conditions, and it seems that improved barrier function and reduced local inflammation could be two of the most significant effects.
So if you want to keep your skin glowing with natural beauty, spare a thought for the billions of live cultures which live on your skin and are vital for its health, and consider probiotic products if you think that your skin bacteria needs rebalancing.
For further tips on how to keep your skin glowing and beautiful, you may like to read this FAQ: Can live cultures help with acne or spots?
1. Gueniche A, Benyacoub J, Philippe D, Bastien P, Kusy N, Breton L: Lactobacillus paracasei CNCM I-2116 (ST11) inhibits substance P-induced skin inflammation and accelerates skin barrier function recovery in vitro. Eur J Dermatol. 2010, 20: 731-7.
2. Kang BS, Seo JG, Lee GS, Kim JH, Kim SY, Han YW: Antimicrobial activity of enterocins from Enterococcus faecalis SL-5 against Propionibacterium acnes, the causative agent in acne vulgaris, and its therapeutic effect. J Microbiol. 2009, 47: 101-9. 10.1007/s12275-008-0179-y.
3. Siver RH: Lactobacillus for the control of acne. J Med Soc New Jersey. 1961, 59: 52-53
4. Kim J, Ko Y, Park YK, Kim NI, Ha WK, Cho Y: Dietary effect of lactoferrin-enriched fermented milk on skin surface lipid and clinical improvement of acne vulgaris. Nutrition. 2010, 26: 902-9. 10.1016/j.nut.2010.05.011.
5. Oral probiotic control skin inflammation by acting on both effector and regulatory T cells. Hacini-Rachinel F1, Gheit H, Le Luduec JB, Dif F, Nancey S, Kaiserlian D.
6. FDA (2016) FDA issues final rule on safety and effectiveness of antibacterial soaps,
7. Kim, S.A. et al (2015), 'Bactericidal effects of triclosan in soap both in vitro and in vivo', Journal of Antimicrobial Chemotherapy, 70(12:3345–3352, https://doi.org/10.1093/jac/dkv275
8. Vandegrift R et al (2017), 'Cleanliness in context: reconciling hygiene with a modern microbial perspective'.Microbiome.5(1):76. doi: 10.1186/s40168-017-0294-2.