Preservatives damage the microbiome, impair skin function, accelerate collagen loss and speed up ageing.

Most skincare products on the market are water-based and that matters more than you think. When you see “water / aqua / eau” (or any of its disguised forms) as the first ingredient on a label, it means the product contains water as its largest percentage. You are not only paying for mostly water BUT the product must also contain a preservative.

Most consumers assume skincare is safe because it is legally sold. But regulations are designed to ensure microbial safety in the product, not long-term biological safety on the skin. Preservatives are tested for how well they kill microbes, not how they interact with fibroblasts (responsible for skin structure), keratinocytes (responsible for the skin barrier), the skin microbiome, or the components of the extracellular matrix. This gap between regulatory intention and biological reality is where the real risk lies for your skin.

Preservatives are not tested for the things that determine long-term skin health — its structure, barrier integrity, cellular function, or microbiome.

The Water Problem in Skincare

• Water is the most common skincare ingredient and the “universal solvent,” often making up 80–98% of a formulation.

• Ingredient labels list components in descending order until 1%; if “water / aqua” is first, it is the dominant ingredient.

• Manufacturers frequently disguise water under terms like eau, hydrosol, fruit extract, juice extract, filtrate, ferment extract, miracle broth. Whether described as distilled, deionized, purified, thermal, glacial, rose, fermented, or anything else, it is still water.

• Multiple water-based ingredients can appear separately using different names creating the illusion that the overall water percentage is lower.

• Many “hero ingredients” are primarily water:
  – Aloe vera is ~98.5–99% water 
  – Snail secretion filtrate 90-99% water

Once a product contains water it must have a preservative or preservation system (multiple preservatives) to stop microbiological growth and this is where the many and multiple problems for your skin begin. 

How to Identify Water by Another Name:

• aqua / water / eau
• hydrosol
• fermented filtrates
• fruit water / juice extract
• rose water / floral waters
• aloe vera gel
• snail secretion filtrate
• miracle broth
• witch hazel
• herbal infusion 
• hydrogel
  

Why Water Means Preservatives and the Consequences for Skin

Bacteria, fungi, and yeasts and any microorganisms require water for growth. To prevent microbial growth in the product formulators, add preservatives.

These preservatives may be synthetic (parabens, phenoxyethanol, formaldehyde-releasers) or “natural” (essential oils, botanical extracts), but their function is identical: antimicrobial activity.

Many brands use the word ‘natural’ to describe preservative systems such as essential oils, sorbic acid, or fermented filtrates. But ‘natural’ describes the ingredient’s origin—not its biological impact. A compound can be natural and still highly cytotoxic (toxic to living cells), allergenic, or disruptive to the microbiome. Nature is full of poisons; origin does not equal safety.

Preservatives make the product microbiologically “safe” in the bottle and extends shelf life. A product preserved against microbial growth does not mean a product safe for long-term skin biology.

Preservatives do not remain isolated in the formula they remain on your skin for hours after application.

Microbiome Disruption, Inflammation & Oxidative Stress

When you apply skincare containing antimicrobial preservatives, those chemicals come into contact not only with your skin cells but also with your skin’s resident microbiome — the community of diverse and mutually beneficial bacteria, fungi, and other microorganisms that perform protective and regulatory functions (barrier homeostasis, pH regulation, immune signalling, lipid metabolism, inflammation control).

• Disrupting the Skin Microbiome. Studies show that chemical preservatives commonly used in cosmetics can inhibit growth or kill beneficial skin-resident bacteria.
• Preservatives Do Not Discriminate. By design they kill or suppress microbes irrespective of whether they are harmful pathogens or beneficial and essential for skin health. Reduction of microbial diversity impairs production of protective lipids, weaken the acid mantle, compromise barrier repair, and make skin more vulnerable to external stressors. It causes microbial imbalance that favours the over proliferation of undesirable bacteria such as those responsible for acne.
• Inflammation & Barrier Dysfunction. Microbiome disruption and chemical irritants together challenge the skin barrier. Repeated exposure triggers low-grade inflammation, sensitisation, redness, and long-term barrier impairment. Indeed, preservatives are among the leading causes of allergic contact dermatitis in cosmetic users. This chronic inflammation slowly degrades skin resilience. If you experience persistent redness, tightness after washing, inconsistent breakouts, flakiness, or  ‘sensitivity,’ it may not be your skin type at all. A real possible culprit is preservative-induced inflammation.
• Oxidative Stress & Cellular Damage. Some preservatives (or their breakdown products) generate reactive oxygen species (ROS) and/or compromise cellular antioxidant defences, potentially damaging DNA, proteins and lipids in skin cells (keratinocytes and fibroblasts), impairing cell function, and accelerating cellular aging. Over time, this oxidative stress may impair collagen synthesis, increase degradation of structural proteins, and slow barrier repair — all of which contribute to premature skin aging and loss of resilience.

A note on “microbiome-friendly,” prebiotic, probiotic, postbiotic skincare

This is where the cosmetic industry stretches into absurdity.

Brands that market water-containing, preservative containing formulas as “microbiome-friendly,” “prebiotic,” “probiotic,” or “postbiotic” are relying on consumers not understanding basic microbiology or not joining the dots.

If a product contains preservatives, you cannot simultaneously kill microbes and claim to support them.

We call bullshit.

Preservatives create a vicious & skin damaging biochemical feedback loop

Preservative
→ microbiome imbalance
→ weakened barrier
→ inflammation
→ oxidative stress
→ cellular injury
→ further barrier impairment

Many people misinterpret this cycle as a “sensitive skin type” — when it may actually be chronic preservative exposure from skincare products including sunscreen.

Preservatives’ Effect on Skin Structure: ECM, Collagen & MMPs

Skin’s structural integrity depends largely on the extracellular matrix (ECM) produced by dermal fibroblasts, primarily collagen (types I and III), elastin, glycosaminoglycans, and other proteins that confer strength, elasticity, and resilience.

When preservatives disturb cell viability or trigger enzymatic breakdown, the ECM can be compromised. This can lead to sagging, wrinkles, thinning, and loss of firmness precisely what many anti-aging products claim to prevent. Key molecular players include:

• Matrix metalloproteinase‑2 (MMP-2): a enzyme capable of degrading ECM components, including collagen types I and III. Controlled by natural inhibitors (TIMPs), but when this balance is disrupted, ECM degradation accelerates.

• Cytotoxicity & Fibroblast Sensitivity: In vitro studies show fibroblasts (dermal cells) are generally more sensitive than keratinocytes (epidermal cells) to many preservatives meaning the dermal matrix (skin structure) may be disproportionately affected.

 MMPs are upregulated by inflammation and oxidative stress This is the exact biochemical pathway responsible for photoaging

Case Study: What Research Actually Shows

A peer-reviewed 2023 study in Cells (“Effect of Commonly Used Cosmetic Preservatives on Healthy Human Skin Cells”) tested phenoxyethanol, parabens, formaldehyde-releasers, a benzoate preservative system, and grapefruit essential oil.

Findings:

• Fibroblasts were more vulnerable than keratinocytes, both are negatively affected.

• Formaldehyde-releasing preservatives caused the most collagen damage

• MMP-2 activity increased with many preservatives

• “Natural” preservatives (essential oils) were equally cytotoxic

The findings were observed at concentrations comparable to those used in commercial products.

Additional research shows methylparaben decreases collagen I/III/VI, increases MMP-2, and induces cell death (cytotoxicity) in fibroblasts at cosmetic-range concentrations.

Preservatives: What They Do and Where They Are Found

Conclusion: The Value of No-Water, No-Preservative Formulations

The evidence strongly supports formulations that eliminate water.
No water = no microbial growth = no preservative = no structural harm from antimicrobial preservatives.

Vitis V Face TonIQ is a concentrated, water-free blend rich in essential linoleic fatty acid multiple sources of antioxidants and bioavailable phytonutrients, because our goal is naturally, healthier skin and that means absolutely no preservatives.

For anyone serious about long-term skin health, barrier integrity, microbiome balance, collagen preservation, reducing oxidative stress and removing accelerated ageing, water-based, preservative-laden skincare products must be eliminated.

That sinking-in feeling after application? It is not absorption it is water evaporating. And as the water disappears, it leaves behind a concentrated residue of preservatives that compromise, disrupt, and damage the biological processes and structural components your skin’s regenerative function depends on to stay healthy.

Key References:

Effect of Commonly Used Cosmetic Preservative on Healthy Human Skin Cells 

Methylparaben-induced decrease in collagen production and viability of cultured human dermal fibroblasts.

Characterization of the decomposition of compounds derived from imidazolidinyl urea in cosmetics and patch test materials

Skin irritation potential of cosmetic preservatives: An exposure-relevant study 

Image credit - Kate Glotova on Unsplash