Most of us are familiar with the visible signs of healthy skin, whether it's texture, firmness, elasticity or a hydrated glow. If you look...and look closely, you'll find one of the most critical (but often forgotten) components of healthy skin - the skin microbiome.
This microscopic ecosystem that inhabits the surface of the skin is made up of a wide variety of bacteria, fungi, viruses and even mites (yes, mites!). 1 While it’s easy to dismiss skin “bugs” as a bad thing, research shows that when skin microbes are part of a balanced and diverse microbiome, they not only live in harmony with our skin, but also support skin health. Conversely, imbalances in skin microbial diversity (AKA dysbiosis) are associated with various deviations in healthy skin function.
Therefore, the microbial balance of the skin affects not only how our skin looks and feels, but also how it functions. Let's take a closer look at the skin microbiome and what we can do to help support it, as well as our skin health, throughout the different stages of life.
Beyond skin deep
The skin is the largest organ in the human body and has a long list of important functions. Besides being our outer image to the world and an expression of our beauty and identity, skin is one of our best defenders. Healthy skin forms a barrier against the harsh threats of the external environment, including but not limited to pollution, allergens, cosmetics, pathogens, UV rays and extreme temperatures., While striving to keep the "bad guys" out, the skin also has functions that keep the "good guys" out, such as moisture, electrolytes, warmth, and all of our inner ingredients! The skin is also responsible for producing vitamin D, an important nutrient needed for bone and immune health.
Getting to know your skin microbes
In order to function as an effective barrier, the skin relies on certain "helpers" to keep everything under control. These helpers include the millions of microbes that inhabit every square centimeter of skin, arguably the most important of them are bacteria. 1 Due to limited space, there is constant competition between good (beneficial) bacteria and bad (disease-causing) bacteria, not only for space to grow, but also for nutrients. Good bacteria help prevent bad bacteria from overgrowing by:
Crowding out bad bacteria
Producing anti-microbial peptides, which can inhibit growth of bad bacteria
Regulating the local immune system
When good bacteria are outnumbered, bad bacteria can disturb skin barrier function by:
Producing enzymes which break down the components of the skin barrier
Dysregulate the local immune system
Encourage further growth of bad bacteria
It’s all about balance
Maintaining a balance between beneficial and non-beneficial bacteria is an ongoing effort. Many factors affect the skin's ability to maintain this important balance, including water intake, diet, and skin cleansing routine. Essentially, the environment we create for our bacteria will determine which bacteria survive and which don't, and our age plays an important role in determining the environment of our skin microbiome.
There’s no place like home
Just like us, our skin bacteria love places to live. Some people prefer dampness (eg, armpits, skin folds), some prefer oiliness (eg, face, scalp, neck, and back), and some prefer dryness (eg, palms and soles). The microenvironments provided by these body parts help certain microbes thrive, often by increasing their preferred food sources.
A life’s journey
Changes in our bodies as we age also contribute to these microenvironmental changes. For example, the super cute, curly skin folds that are common in babies can generate a lot of heat and moisture, which can attract the growth of hygrophilic microbes like Staphylococcus aureus. On the other hand, in our teenage years, hormonally driven overactive sebaceous glands attract the growth of oil-absorbing bacteria such as Bacillus acnes. As sebaceous gland secretions decrease in older adults, the same bacterial populations naturally decrease.
These age-related microbial changes can lead to common skin imbalances associated with specific life stages, such as teenage acne.
It all starts at birth
Our skin microbiome is influenced not only by our microenvironment, but also by our macroenvironment—the environment in which we find ourselves in the wider world.
From the barely bacteria-free environment in the womb to the microbial zoo of the outside atmosphere, birth is an introduction to the world of the microbiome. Despite the differences in the way we enter, there are significant microbial differences between vaginal and caesarean sections.
During the first 4-6 weeks of life, the infant skin microbiome begins to form, as it expands and diversifies until it finally stabilizes around age 3. Different body parts begin to exhibit their own unique microbial patterns, and the microbial community begins to reflect our individual differences, some of which can be determined by:
Diet – such as macronutrient (e.g., carbs, protein and fats) and alcohol intake
Use of emollients and washes
Living location and much more
It is well known that the human microbiome is largely influenced by the world around us, but scientists have found that age is one of the strongest determinants of microbial patterns. In fact, a 2020 study found that skin microbiome samples can predict a person's age to within 4 years of accuracy.
Supporting skin microbial health through the ages
The skin microbiota is dynamic and adaptive, responding to active dietary and lifestyle interventions. Steps you can take to support a healthy and balanced skin microbiome include:
Nurture your gut – Studies have shown that people with acne are more prone to dysbiosis than healthy people. He is believed to have been influenced by a Western-style diet rich in refined carbohydrates, saturated fats, dairy products, chocolate and low in omega-3 fatty acids. 5 Eating a diet rich in plant foods, antioxidants, fiber, and essential fatty acids directly supports not only skin health, but also gut and skin microbiome health.
Stay hydrated – Drinking enough water every day is an important part of general health maintenance. For those who drink less water or are at higher risk of dehydration due to exercise or older age, several studies have shown that adding at least 100ml to 2 liters of water per day may help support deep water skin hydration and elasticity Healthy skin while reducing dryness and roughness.
Strengthen your skin barrier – Healthy skin barrier function is as important to the skin microbiome as it is to the skin. Collagen supplements have been shown to support skin integrity and elasticity.
Consult your healthcare practitioner for more specific health advice on how to care for your skin microbiome.
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