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Taking care of your skin biome

What is it? skin biome is a new trend in skincare. Once upon a time, we were only aware of one bacterial species in our skin: the acne bacteria. So much so that most acne treatments were intent on killing anything and everything! The result of this practice was a lot of people with “sensitive skin”.

What happened since that, more innocent time?  Once probiotics became ubiquitous in people with (or without) GI problems, the skin care industry saw the potential for new sales. The big obstacle was that the skin care industry could not sell products containing bacteria, so they went into “prebiotics“.

Myths and facts about the skin biome

First of all: yes, the skin microbiome exists (please see my other posts on the subjects, linked below). And yes, we should take care of it. Actually, the skin biome can take good care of itself, with some exceptions. What are the exceptions?

Alteration of the skin biome by its owner! This will show as “skin sensitivity”

Acne    We don’t like acne, and have searched the scientific literature to find the best ingredients that. combined, will keep the acne bacteria in check and promote healthy recovery and healing.

Seborrheic dermatitis: excess sebum secretion will promote bacterial growth. It’s best to control sebum secretion (T-zone serum will help which in turn will normalize bacterial composition)


How can Skin Actives help you?

We don’t use “kill everything” ingredients (like benzoyl peroxide).

We make cleansers that respect your skin and don’t push the skin’s pH up (“natural deodorants” do).

We are up-to-date with the science of skin physiology. We prefer to “push out” bad bacteria with the right chemicals, just like other bacteria do, rather than oxidizing the microbiome (and the skin) to death.

We are not allowed (by law) to sell (or give away!) products containing bacteria.  But we use prebiotics, i.e., products containing chemicals that will discourage the growth of “bad bacteria” and fungus. We produce bioferments and plant extracts and also add some pure chemicals known to discourage the growth of acne bacteria and other bad actors. Look for Skin Actives products containing sea kelp bioferment and kefir ferment for bacteria-free (but nutrient-rich) filtrates that favor the good bacterial partners that your skin needs.


DISCLAIMER: These claims have not been evaluated by the FDA and are not intended to diagnose, cure, treat or prevent any disease.

From my book

It used to be that we only discussed bacteria when speaking about infections. It was all about acne in skincare and how to kill the recently renamed acne bacterium, Cutibacterium acnes (a.k.a. Propionibacterium acnes). But now, you can see bacteria and the “microbiome” everywhere in magazines that advertise skincare products.

Bacteria are essential to the human body’s function, and many bacteria species live in us and on us. We are familiar with the negative effect of taking oral antibiotics on our gastrointestinal tract and the flora that resides there; your doctor may suggest you take a probiotic, a mix of “good,” live bacteria, to help recover intestinal health.

Like our intestine, our skin includes an ecosystem, the skin microbiome—that includes trillions of microbes. Most of these microbes are not dangerous; they’re more like an outer layer of skin we are not aware we carry, but they influence everything from acne, eczema, and dry skin to how we smell.

The aim of skincare should be to keep a healthy microbiome, not “overcleaning” to kill every single bacterium. A widespread modern affliction, sensitive skin, is usually caused by overcleaning, which removes the epidermis’ external layers that make up the skin barrier, plus the bacteria living in it.

Human skin functions as a physical barricade to stop the entry of pathogens and hosts innumerable commensal organisms. Commensal means living in a relationship where one organism derives food or other organisms’ benefits without hurting it. The skin cells and the immune system regularly interact with microbes maintaining equilibrium, despite continuous changes in the environment. Many factors influence the species composition of the microbiome, like diet, gender, ultraviolet radiation, even your family.

In the case of crops, it is possible to manipulate soil bacteria to prevent infection and stop the dissemination of viral and bacterial diseases. It should also be possible to control the bacteria that live in and on our bodies to prevent infection by “bad” bacteria, but this is a huge task. Why? Sometimes we don’t even know which bacteria are growing in the system we are studying. In the skin, many bacterial species will not grow well in culture, so a complete identification of bacteria requires DNA technology. Now we know that Proteobacteria, Actinobacteria, Bacteriodetes, and Firmicutes dominate dry skin. Moist areas are rich in Staphylococcus and Corynebacterium spp. There is less bacterial diversity in oilier areas, suggesting that only a few bacterial communities, like Propionibacterium, can flourish under those conditions. Scientists are also learning that rough distinctions may not be enough and that different strains of C. acnes may be associated with acne while others may be protective.

Scientists are getting to know more about the skin microbiome, but it will take a lot of research and a long time before we know enough to effect a positive change. As usual, changes for the worse are easy to get, and “natural” antiperspirants show that using bicarbonate to increase pH push the balance away from natural bacteria and favors the growth of more dangerous bacteria, even yeasts. You may smell nice, but your armpits may get red, rashy, and itchy.

Just in case you are still using them, stop using antibacterial soaps. Frequent use of some antibacterials will promote the development of bacteria resistant to antibiotics, promoting the proliferation of drug-resistant infections, a scourge of medicine. The skin microbiome is best left alone unless its disruption becomes apparent, like with acne.

As mentioned above, a probiotic is a mix of live bacteria that we ingest to improve the digestive system’s health. Everyday use of probiotics is when we use them during or after taking an antibiotic to compensate for the disruption of the natural digestive flora. What about the skin? You can’t buy probiotics for the skin. The FDA (Food and Drug Administration in the USA) sets strict limits on the number of live bacteria present in cosmetics. This rule makes sense: we must avoid excess or dangerous bacteria from entering our bodies. With a stomach operating at a very low pH, our digestive system is well equipped to kill bacteria. Conversely, our skin is not well equipped to kill dangerous bacteria. In the old times (as I always say, older times were not better), contaminating bacteria present in cosmetics without preservatives caused terrible damage, including blindness,

We can’t do topical probiotics, but we can do topical prebiotics. What is a prebiotic? In food, they are chemicals that induce the growth or activity of beneficial bacteria and fungi. Prebiotics like natural food fibers can alter organisms’ composition in the gut microbiome. For our skin, what would be the equivalent? We can “fake” it. Some Staphylococcus epidermidis strains can ferment carbohydrates to produce succinic acid, a chemical that has potent anti-S. aureus and anti-C. acnes activity. This fact is relevant to acne treatment because, in theory, we could improve skin health and control acne by using prebiotics like succinic acid and glycerol that will discourage C. acnes from spreading.

As I said above, we can’t use probiotics (live bacteria) on our skin for excellent reasons, but we can use prebiotics, and we already do! The Skin Actives Scientific acne control products contain ingredients that modify the skin environment to make it less hospitable to acne bacteria. We can do more, and we will continue to improve our products as we learn more about the skin microbiome.

Our main prebiotic ingredient is “sea kelp bioferment”; this is the INCI name, a more suitable name would be kelp Lactobacillus ferment. The sea kelp bioferment we use as a base for many of our products starts with the sea kelp. This plant material is rich in biochemical components that are already beneficial to our skin. But then we cultivate yogurt bacteria in this broth. What do we gain with this extra step? The microorganisms will make their valuable biochemicals and enrich the mix with prebiotics that will benefit the skin in other ways. They supply more vitamins and building blocks that our skin will use to make its proteins (collagen, elastin, and more), polysaccharides, and DNA. We are already experimenting with using a kefir mix to provide a different prebiotic base serum.

Take-home lesson: don’t attack what you don’t know. Don’t use strong oxidants or anti-bacterial products, or remove the external layers of the epidermis that constitute the natural skin barrier. Don’t change your skin’s pH with “natural” antiperspirants. If you do, you may get into trouble because you will be disrupting the natural equilibrium achieved by the skin and its microbiome.


In my blog

Microbiome, probiotics and prebiotics

Questions and answers about the skin microbiome and pre- and probiotics.