Prebiotics may play a role in protecting against skin diseases, says a recent study.
Taking a regular dose of prebiotics to improve the diversity of the gut microbiome and therefore digestive health has become relatively commonplace, but few people realize that the microbiome of the skin could benefit from similar attention.1 The skin microbiome contains ten times as many bacteria cells as human skins cells, and studies show that when there is less diversity of the skin microbiome, there is an increased risk of certain skin diseases.2
People are less aware of prebiotics - supplements or foods that contain a nondigestible ingredient that selectively stimulates the growth and/or activity of indigenous good bacteria. “When it comes to skincare, prebiotics might be more important,” says Heather Woolery-Lloyd, M.D., director of ethnic skincare in the department of dermatology and cutaneous surgery, Miller University of Miami School of Medicine.
Prebiotic agents that could help rebalance the skin microbiome include water, carbon source (sugars, e.g., mannose), nitrogen source (amino acids) and oligoelements (calcium, magnesium, manganese, sulfur, selenium, etc.), were discussed by Dr. Woolery-Lloyd during a broader presentation on cosmeceuticals at the Skin of Color Update in New York in September.
Thermal waters contain unique minerals based on where they originate. Some of the best evidence relates to the use of an emollient containing a particular proprietary thermal spring water from a specific town in France, which has high levels of a variety of minerals including calcium, magnesium and selenium.
“They’ve done over 12 studies looking at how products containing this thermal spring water containing these prebiotics and minerals that feed the good bacteria, and have proven that this thermal spring water helps to restore a healthy microbiome in the skin,” says Dr. Woolery-Lloyd. “Probably the best study to show compared it to a regular moisturizer available in Europe.”3
Sixty patients with moderate atopic dermatitis were treated with a topical steroid for the first 15 days and then randomized to an emollient-containing thermal spring water associated with mannose or another moisturizer widely used in Europe. After 28 days patients treated with the thermal spring water product had significantly increased levels of the good bacteria Xanthomonas in their skin microbiome and reduced levels of Staphylococcus compared with those treated with the regular moisturizer. Significantly fewer patients treated with the thermal water product experienced flareups and, when they did, they were less severe than in patients treated with regular moisturizer.
These findings suggest “prebiotics may play a role in feeding the good bacteria and restoring a healthy microbiome and protecting us from skin diseases.” Most the work regarding use of prebiotics to improve the skin microbiome has been focused on atopic dermatitis because a healthy microbiome is considered an important component of a healthy skin barrier, she says. However, there is emerging data for psoriasis, and patients with other skin diseases like rosacea may also benefit from prebiotics.
“Atopic dermatitis is most common and more severe in children of color, particularly African American children, so although this concept of improving the microbiome would be helpful in all people with atopic dermatitis, African American children are a patient group that is particularly vulnerable,” she adds.
Dr. Woolery-Lloyd suggests a number of well-known and less well-known cosmeceuticals that can be beneficial for skin of color including hyaluronic acid, which binds with water and is a useful plumping agent; vitamin E with its antioxidant properties, vitamins C and silymarin, which both have antioxidant and skin brightening properties; niacinamide, which is used widely in dermatology for fading dark spots and for its antiaging properties.
“Niacinamide, which is a tried and tested product, has anti-glycation properties,” she says.4 Skin brightening and rejuvenation occurs by reducing advanced glycation end products (AGEs). Hexylresorcinol, a common ingredient in cough medicines, as it has anaesthetic and antibacterial properties, is also used in skincare because of its anti-glycation and skin brightening properties.5
As people age, more proteins in the body bind with sugars (glycated) to produce AGEs; these contribute to age-related diseases. For example, diabetics have high levels of AGEs in their blood, and their blood vessels have high levels of glycated protein, which become stiff and less supple predisposing them to heart disease.
Skin UV radiation and smoking cause sugar to bind to protein creating glycated proteins that are not as functional and are more brittle. Glycated proteins are also consumed in the diet particularly from foods that are barbecued, grilled or fried.
In the skin, the protein most likely to become glycated is collagen, but other proteins such as fibroblasts are also affected. The first glycated collagen is detectable in skin around the age of 20 and levels then increase by around 3.7% every year.
Stimulation of AGE receptors activates NF-kÃ which leads to an inflammation cascade through transcription of many proinflammatory genes. In a vicious cycle NF-kÃ also increases further expression of AGE receptors, which stimulates further NF-kÃ.
Niacinamide is popular in products focused on skin of color, Dr. Woolery-Lloyd says, and vitamin C has skin brightening properties so it is particularly helpful.
1. Naik S, Bouladoux N, Wilhelm C, et al. Science. 2012;337(6098):1115-9.
2. Kong HH, Oh J, Deming C, et al. Genome Res. 2012;22(5):850-9.
3. SeitÃ© S, Zelenkova H, Martin R. Clin Cosmet Investig Dermatol. 2017;10:25-33.
4. Vinson JA, Howard TB. J Nutr Biochem. 1996; 7(12):659-63.
5. Chaudhuri, Ratan. (2015). Hexylresorcinol: Providing Skin Benefits by Modulating Multiple Molecular Targets. In: Sivanani RK, Jagdeo J, Elsner P, Maibach HI, eds. Cosmeceuticals and Active Cosmetics. 3rd ed. Boca Raton, FL: Taylor & Francis Group; 2016.