As one of the very first brands to deploy microbiome science in its formulations, Esse has witnessed the encouraging rise in awareness of probiotic skincare recently. As more people learn of the skin microbiome’s importance and more skincare brands enter the space, it’s important to develop our understanding of the ingredients that make probiotic skincare so promising. While more products are starting to include ingredients that involve beneficial microbes, not all these ingredients are true probiotics, and not all are created equal.

Let’s explore two such ingredients and the differences between them:

• Postbiotics are non-living preparations made from beneficial microbes. While they provide some skin benefits, they are not the same as those provided by living microbes.

• Probiotics are living, active microbes that are beneficial to our health.

Many products advertised as “probiotic” don’t contain true probiotics, but instead include postbiotics, which are much easier to add to skincare formulations.

The reason it’s important to distinguish between these two ingredient types is that live probiotics provide an impressive set of benefits, some of which cannot be provided by non-living microbes.

Here are some areas in which live probiotics perform differently from postbiotics:

Live probiotics colonise skin and compete with unwanted microbes, providing active defence.

Applying live probiotics places living microbes on skin’s surface, where they actively defend their newfound home from potentially harmful external microbes. While postbiotics can provide some limited defence, they can’t react to incoming threats as well as live probiotics, which compete against harmful microbes for space and nutrients, making invasion much more difficult.

Live probiotics actively produce substances that match your skin’s unique situation.

True probiotics actively produce substances that take part in skin’s natural function. These substances are varied, providing a range of benefits such as sending healthy signals to skin’s immune system, feeding other beneficial microbes, adding an extra layer of defence, and strengthening skin’s barrier. Because true probiotics are alive, they adapt to your skin’s current state, producing these substances differently, according to the situation. Postbiotics don’t produce any substances, but contain some of them at set levels, depending on how they were produced.

Live probiotics communicate actively with your immune system to calm inflammation.

Research has revealed that there is constant cross-talk between our immune systems and our microbial partners, as they work together to ensure that immune activity is properly managed. Our immune systems can’t function without this microbial communication. While postbiotics may contain substances that have some immune effects, they don’t provide the real-time communication with the immune system that makes live probiotics so powerful in maintaining healthy immune function.

Live probiotics produce the right substances to fight off the harmful microbes your skin encounters.

Antimicrobial peptides (AMPs) are a group of substances that fight off unwanted microbes. Skin and its microbiome work together to produce these defensive compounds. Live probiotics can actively contribute to this collaboration by producing the right AMPs at the right time to defend from a harmful invader. Postbiotics can be produced in a way that maximises AMP content but can only include them at set levels, not responding to the dynamic situation in skin.

Live probiotics produce acidic substances that maintain your skin’s pH.

Many species of live probiotics produce acidic substances such as lactic acid, short chain fatty acids, and Hyaluronic Acid, which keep the pH of their environment low. Skin is naturally acidic, which is crucial in avoiding the growth of unwanted microbes. While live probiotics can work to achieve and maintain an optimal skin pH, postbiotics only contain acidic substances if they are made in a certain way, so can’t dynamically shift skin pH.

Live probiotics produce enzymes that play important roles in skin health.

The structure of our skin is influenced by the microbes that live on and in it. For example, some microbes make proteases – enzymes that break down proteins to help old skin cells shed at a healthy pace. Others produce lipases – enzymes that break down fatty acids in the skin’s natural oils, creating key signalling compounds. Live probiotics can generate a range of these enzymes, adapting to the skin’s current conditions to help balance and improve its overall function. In contrast, postbiotics might include some enzymes, but they can’t adjust to the skin’s environment and only perform fixed tasks. Plus, certain ways of making postbiotics can damage or inactivate those enzymes, making them useless.

Live probiotics stop harmful microbes from forming disease-causing biofilms on your skin.

Some microbes that are harmful to skin, such as Staphylococcus epidermidis, can group together in large communities, forming resilient structures called biofilms. Once established, pathogenic biofilms can be very difficult to eliminate and often cause treatment-resistant skin conditions. Some live probiotics can interfere with the way harmful microbes communicate, blocking the formation of these biofilms. Postbiotics can’t protect skin in this dynamic, responsive manner.

Live probiotics bolster your skin’s barrier, helping you stay hydrated and resilient.

The skin serves as a vital barrier, shielding the body from harmful substances through its multifaceted components. Live probiotics enhance this barrier by strengthening tight junctions to tightly bind skin cells, supporting the stratum corneum through increased filaggrin production and healthy desquamation, bolstering chemical defences with antimicrobial peptides and acidic compounds, and fostering a balanced microbiome for robust protection. Unlike postbiotics, which offer limited benefits due to their static nature, live probiotics dynamically adapt, simultaneously delivering comprehensive support to all barrier elements for optimal skin health

Live probiotics reduce oxidative stress and UV damage in your skin.

Postbiotics are useful ingredients for antioxidant defence, often providing more concentrated antioxidants than live probiotics produce. However, live probiotics can protect skin from reactive oxygen species and free radicals in more varied ways. They can stop UV damage from suppressing immune function, calm the inflammatory cascade that oxidative stress can cause, produce antioxidants directly, and promote the expression of genes that allow skin to produce its own antioxidant compounds.

As we mentioned earlier, live probiotics are difficult to include in skincare products. This is a challenge only a few brands have managed to solve. When a brand claims to be “probiotic”, it’s worth checking if they’ve really included living microbes in their products.
Tip: Ask how many colony-forming units (CFUs) per mL they have included – that’s a measure of the number of living probiotic cells in every mL of the product.

It’s not that postbiotics aren’t useful – they certainly provide some impressive benefits and can be used in almost any product. It’s just that true probiotics are living, responsive organisms. Like any living system, they are immensely complex in their function, and they adapt to their environment. This means that they provide skin benefits in many different ways, affecting every aspect of skin health – and they do so in an adaptable way, responding to the conditions in each unique skin. It’s actually amazing that advances in technology have allowed us to use these microbial collaborators as skincare ingredients.