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Yes, but not by adding them to a normal cream. I have written about why this is difficult. This one is about what people have actually done about it, including the approaches that did not work.
The short answer
Every workable solution is a way of managing one variable: water. Dry the cells, keep water activity low, wrap them in something, or keep them apart from the water until use. But water is also what wakes them up, so any approach that never rehydrates them has kept them alive without ever letting them work.
In an earlier article I set out the four things working against viability in a cosmetic: water, preservatives, temperature and oxygen. That article was about the problem. This one is about the engineering, which is what I actually do for a living.
One fact about bacterial cells explains every approach below.
A bacterial cell with access to water becomes metabolically active. It starts consuming, producing and eventually exhausting itself. In a jar sitting on a shelf for a year, that is a death sentence, and it is a death sentence delivered slowly enough that nobody notices until the product is tested.
Take the water away and the cell goes dormant. Metabolism effectively stops. It is not dead, it is waiting. Every technology below is a different answer to the same question: how do you keep the cells dry enough to wait, in a product that is eventually going to be wet?
Approach one
Freeze-drying
Also called lyophilization. The culture is frozen, then the ice is removed under vacuum without ever becoming liquid. What remains is a dry powder of dormant cells. This is how nearly every live microbial product on the market begins, in supplements, agriculture and cosmetics alike.
The catch: freezing and drying are both violent for a cell. Ice crystals damage membranes, and dehydration pulls water away from structures that need it. So the process is never run on cells alone. It is run with protectants, and the protectant system does a great deal of the work. Trehalose, sucrose, skim milk, sorbitol and ascorbate all appear in the literature in different combinations, and outcomes vary widely with the choice and with the organism.1 There is no universal recipe and there is always losses.
Approach two
Controlling water activity
Drying is not a yes or no. What matters is water activity, written as aw, which measures how available the remaining water is rather than how much of it there is. It runs from 0 to 1.
The numbers are specific and they matter. Survival is generally best between about 0.1 and 0.3.2 Above roughly 0.25, mortality climbs, because there is enough available water to restart metabolism without enough to sustain it. For long storage, lower still is better.
Why this is the number to ask about: a product can be a dry powder and still be too wet. Water activity is the measurement that tells you, and it is the one a formulator actually works to.
Approach three
Microencapsulation
Wrap each cell, or a small cluster of cells, in a protective shell. Alginate, chitosan and various polysaccharides are common. The shell buys time against moisture, oxygen and pH.
The catch: it is a delay, not a solution. A capsule sitting in an aqueous cream for twelve months is a barrier being slowly worn down. Encapsulation is genuinely useful for getting cells through a hostile passage, which is why it works so well for oral supplements getting through stomach acid. A year on a bathroom shelf is a different kind of ask.
Approach four
Use an organism that does not care
Some bacteria form spores. Bacillus species in particular can survive heat, drying and time in a way that lactobacilli simply cannot. If stability is your only problem, a spore-former solves it almost for free.
The catch, and it is a real one: you have changed the organism, so you have changed every other question too. A dormant spore is not metabolically active. It has to germinate to do anything, and whether that happens on skin, and what follows if it does, is a separate body of evidence from the one covering lactic acid bacteria. Solving stability by switching organisms is legitimate. It is not the same product.
Approach five
Keep them apart from the water entirely
Rather than protecting cells inside a wet formula, do not put them in one. Keep the organisms dry in a separate compartment and combine at the point of use.
Disclosure: this is the approach my own products use, so treat what follows as an interested party describing their own choice.
The catch: it moves the problem rather than eliminating it. You now need packaging that keeps two things separate and then mixes them reliably, which is more expensive and more complicated to manufacture. And once activated, the clock starts. That is why activated products carry a use-by window rather than a shelf life.
Approach six
Suspend the dry cells in oil
Take freeze-dried powder and disperse it into an anhydrous base. An oil, a balm, a stick. No water means no metabolic activity, and no water also means no preservative is needed, so the conflict described later in this article disappears.
It works, on its own terms. Anhydrous systems have been reported to hold cells in a dormant state for many months, and oil bases have retained viable counts better than dry powder controls over comparable periods.
The catch is the whole next section, and it is the one I find most interesting in this entire field.
Every one of these has a cost. That is not a flaw in the field, it is what engineering looks like. Anyone presenting a solution without a trade-off has left something out.
Here is the step almost nobody talks about, and it is the one that decides whether any of the above matters.
A freeze-dried cell is not simply asleep and otherwise fine. It is dehydrated, its membrane is under strain, and its metabolism has stopped. To do anything at all, it has to be rehydrated. And rehydration is not a formality. It is a process with conditions, and it can be done badly.
When water reaches a dried cell, it moves in fast. The cell goes from dry and dormant to hydrated within seconds, and if it happens too abruptly the osmotic shock ruptures membranes. Osmotic shock during reconstitution is one of the main causes of loss when a freeze-dried culture is brought back.3 Rehydration medium, volume and temperature all change the outcome. An inadequate rehydration step produces poor viability even after a well-run drying process.
The distinction that matters
Viable means the cell could recover if conditions allowed.
Functional means it has recovered and is metabolically active now. Work on lyophilized L. plantarum found that rehydrating cells before application improved their functional properties, which is to say the rehydration step itself did work that dryness alone did not.4
In an oil-based product, the cells never go through that step. They are dry when they go into the jar, dry in the jar, and dry when they land on your face.
Proponents of the approach describe the mechanism honestly enough: the organisms are expected to work their way out of the oil matrix and be activated by the limited moisture of the stratum corneum. Read that again as a formulator would. Every part of it is uncontrolled.
How much moisture is on the surface of your skin depends on the season, the room, the time since you washed, where on your body you applied it, and whose skin it is. There is no dose of water, no defined temperature, no controlled rate. Some cells may rehydrate. Many will not. And the ones that do not remain exactly as unresponsive on your skin as they were in the bottle.
So the count can be perfectly true and still not describe what happens on your skin. Preserving viability by never waking the cells up is a real achievement, but it answers the storage question by deferring the activation question.
This is not an argument that oil-based systems are dishonest. Viability is genuinely maintained and the data supporting that is real. It is an argument that viability and activity are two different claims, and only the first one has been demonstrated.
Others have reached the same conclusion from the other direction and built “just add water” systems, where a dry powder is combined with an aqueous phase at the point of use precisely so that rehydration is a controlled step rather than an accident.5 The disclosure from earlier applies again here, since that is the same logic my own products use.
One practical footnote. Anhydrous formats also have to be something people want to use. Oils, balms and sticks are a small share of what most people reach for, so solving the problem this way narrows the audience before you have sold anything.
Preservatives.
A cosmetic containing water needs preservation, because water in a jar that gets opened daily and touched with fingers will grow things you did not invite. Preservatives work by killing microorganisms, and they have no way of distinguishing the organisms you added deliberately from the ones that arrived by accident.
There is no encapsulation clever enough to fix this, because the two requirements are directly opposed. Which is why the approaches that actually work are all versions of keeping the cells out of the preserved phase, rather than protecting them within it.
Read that list again and notice what it demands. Specialist drying equipment. Protectant formulation work. Water activity measurement. Often bespoke packaging. Stability testing across a year at multiple time points, which by definition takes a year.
In a review published this year with a colleague, we looked at where the technical literature actually sits. Most of the formulation work in this area has happened inside companies rather than in the open literature, and best practice in cosmetic formulation, storage and application is still largely oriented toward chemistry rather than biology.6 Which is a polite way of saying that the field is still working out how to make products that are alive, using rules written for products that never were.
Worth saying plainly
None of this is a reason to be impressed by a product simply because it is difficult. Difficulty is not a benefit. It is only the reason the answer to the question in the title is “yes, but almost nobody does”.
✓ How are the organisms kept viable? A company that has solved this can describe the mechanism in one sentence. A company that has not will talk about the organisms instead.
✓ Is there a preservative in the same phase as the cells? If yes, ask how both are meant to work.
✓ If the product is anhydrous, when are the cells rehydrated? If the answer is “by your skin”, that is not a controlled step and the cells may never become active at all.
✓ Is there a count, and at what point in time? At manufacture is easy. At the end of shelf life is the one that matters.
✓ If it is a spore-former, is that stated? It is a reasonable choice and it should be an open one.
Key takeaways
✓ Water is the organizing variable. Cells with water are active and exhaust themselves. Cells without it wait.
✓ Freeze-drying is where nearly every live product starts. The protectant system does much of the work, and losses are always significant.
✓ Water activity, not moisture content, is the number that predicts survival. Roughly 0.1 to 0.3, and lower for long storage.
✓ Encapsulation delays the problem. It does not remove it.
✓ Spore-forming organisms solve stability by being a different kind of organism, with a different evidence base.
✓ Preservatives remain unsolved. Every working approach keeps the cells out of the preserved phase rather than protecting them inside it.
✓ Oil and other anhydrous bases do preserve viability, and they remove the preservative conflict entirely.
✓ But a dried cell has to be rehydrated to do anything, and rehydration has conditions. Leaving it to whatever moisture happens to be on your skin is not a controlled step. Viability and activity are two different claims.
References
Links go to the peer-reviewed record. You are welcome to check my work.
1. Impact of protectants on the storage stability of freeze-dried probiotic Lactobacillus plantarum. Compares protectant formulations and their effect on survival through drying and storage. PMC6484043
2. Higl B, et al. Impact of water activity, temperature, and physical state on the storage stability of Lactobacillus paracasei ssp. paracasei freeze-dried in a lactose matrix. Biotechnol Prog. 2007. doi:10.1021/bp070089d
3. Rehydration conditions and viability of freeze-dried lactic acid bacteria. Cryobiology. Osmotic shock during reconstitution is identified as a principal cause of loss, with survival affected by rehydration volume and temperature. ScienceDirect
4. Rehydration before application improves functional properties of lyophilized Lactiplantibacillus plantarum HAC03. Microorganisms. 2021;9(5):1013. doi:10.3390/microorganisms9051013
5. Gruber JV, et al. Living, quiescent Lactobacillus plantarum Lp90 probiotic, delivered topically to full thickness tissues in vitro via a just-add-water cream delivery system, stimulates the expression of elastin protein. J Cosmet Dermatol. 2023. doi:10.1111/jocd.15927
6. Rezaei F, Rollin JA. A microbial formulation perspective on probiotic skincare: viability, challenges, and current approaches to maintain probiotic viability. Biotechnol Bioeng. 2026. doi:10.1002/bit.70268
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About the author
Dr. Farzaneh Rezaei, PhD, Microbial Formulation Scientist
Founder of Fafabiotic, with two decades developing microbial technologies. She writes Ask the Scientist to explain the science behind probiotic skincare without the marketing layer.
Educational content only. This article is not medical advice and is not intended to diagnose, treat, cure or prevent any disease.
