11. Apr, 2018

Skin and the immune system

It's been a crazy couple of months. Among other things, I've been trying to explain the importance of not disrupting the skin's microbiome and natural fatty barrier to my girls, as they've just taken an interest in make-up, being tanned & all things that make them look/smell nice. Ah, tweens... 

Until you start seeing your body at the microscopic level (see image), it's something you probably don't think twice about, but along with pathogens, chemicals such as sodium lauryl sulphate and even essential oils found in personal care products including body washes, shampoos, baby wipes, sunscreen, tanning products etc have adverse effects on human skin and can hang around for a while causing damage. This is particularly problematic for young skin, but is just as important for the rest of us. Now add to that the use of anti-bacterials, and you might begin to see how our skin is being assaulted in ways it's never been before. Could there be a link between this and the increases in allergies we've seen over the last 20 years? 

The 'Leaky skin' hypothesis is similar to that of 'Leaky Gut', with dry, cracked skin offering an entry point for allergens/pathogens (Brown 2012). Now a study by Northwestern University Feinberg School of Medicine has confirmed a link between skin exposure and the development of allergies (Walker et al. 2018). Though this is common sense to anyone that has training in human physiology such as myself, it's not something most of us think about. Yes, we need to use sunscreen to avoid developing skin cancer, and those of us with dry skin may need a moisturiser, but we need to choose wisely. Admittedly the study was in mice, but that's where most research begins before moving onto human trials - if finances permit that is! 

Fragrance and paraben free sunscreen has been available for a while, and simple sorbolene without perfume is a perfectly effective moisturiser. There are numerous brands of natural skincare & makeup, so leave the cheap & nasty stuff on the supermarket shelves and look after your largest organ - it's your immune system's first line of defence! 

References: 

Brown, E 2012, SCALY SKIN, DRIPPY NOSE, WHEEZY BREATHING: COINCIDENCE OR CONNECTION?, Graduate School of Arts and Sciences at Harvard University blog, ,<http://sitn.hms.harvard.edu/flash/2012/issue109/

Harvard University 2012, Immune response dysfunction in atopic dermatitis, <https://i0.wp.com/sitn.hms.harvard.edu/wp-content/uploads/2012/01/immune-response-dysfunction-in-atopic-dermatitis.jpg?w=867>

Walker et al. 2018, 'Mechanism for initiation of food allergy: Dependence on skin barrier mutations and environmental allergen costimulation', The Journal of Allergy & Clinical Immunology, <http://www.jacionline.org/article/S0091-6749(18)30233-1/fulltext>