Digesting Research on the Gut-Skin Axis
Medical researchers have recently reported on various correlations between digestive system disorders and skin problems.
The ‘gut-brain axis,’ a term denoting the connection between gut health and psychological conditions, like depression or anxiety, was first introduced in 1930. *¹ The connection between the two is now widely accepted.
More recently, the ‘gut-skin axis’ has become a fertile topic of research.
The mechanisms involved in this latter interplay are yet to be fully explained, but for the guy on the street (i.e. myself), for whom the relationship between gut and skin health has always been a matter of simple Newtonian physics, the time has come to let go of some misconceptions.
For instance, at puberty we learned that too much pizza and burgers would cause us to break out in pimples, right? In our teen years we saw the results of junk food binging the very next day. Fat from that double cheeseburger, shake and fries had proceeded from our bellies to the skin pores of our nose, chin and cheeks, and – voilà – produced a fresh crop of paps and zits. We had all kinds of scrubs and creams to scrape away or conceal the problem, even as we realized that if we could just break the burger joint habit, those ugly blemishes would stop sabotaging our dating prospects.
But dermatologists now tell us that such thinking is only partly correct. While a healthy diet is surely of great importance for maintaining a clear complexion - and a healthy epidermis in general - why this is so is a pretty complicated matter.
First, the skin is an organ in and of itself, in fact the largest organ of the human body. *² Like the gut, it is inhabited by vast numbers of bacteria, fungus and viruses – collectively, a microbiota - some friendly, others not.
For instance, acne is associated with an unfriendly bacterium, Propionibacterium acnes, that inhabits the skin. (The kids with acne in high school knew this; we without the affliction were not so enlightened.) But in those days, no one theorized that gut health might also play a role. In fact, it is now thought that a gut overpopulated with bad bacteria “impairs the absorption of fats, proteins, carbohydrates and vitamins”, *¹ and thus plays a major role in the proliferation of acne.
Gut disorders and skin conditions have been linked in other ways, as well. Psoriasis is ‘commonly’ accompanied by irritable bowel syndrome (IBS); atopic dermatitis, the most common childhood skin condition, is linked to an insufficient immune response caused by a weakened gut biome; pyoderma gangrenosum, a very serious skin condition, is much more likely to occur in people with serious bowel disorders, such as ulcerative colitis. Up to 15% of patients with gastrointestinal inflammation have skin conditions of one kind or another.
The above-referenced reports also discuss the benefits of probiotics on gut health. It seems that along with a healthy diet, our guts – and skin – can use a little help from the right supplement.