If there is one nutrient your skin cannot function without, it is Vitamin A.

Not because it is trendy. Not because it is a marketing term. Because at a cellular level, Vitamin A is involved in nearly every process that keeps skin healthy, resilient, and able to repair itself. When your levels are adequate, your skin does its job. When they are depleted — which happens to most people, most of the time — the consequences show up in ways that are easy to mistake for simply "aging."

Understanding how Vitamin A actually works in the skin, and what depletes it, changes the way you think about skincare entirely.

What Vitamin A Actually Does in the Skin

Vitamin A belongs to a family of compounds called retinoids. In the skin, it functions primarily by binding to receptors inside skin cells — called retinoic acid receptors (RARs) — and directly influencing how those cells behave. This is not a surface-level effect. Vitamin A works at the level of gene expression, telling cells what to do and when.

The key functions it regulates include:

Cell Turnover

The skin renews itself through a continuous process of cell production and shedding. New cells are generated in the deepest layer of the epidermis, gradually migrate to the surface, and are eventually shed. This cycle takes roughly 28 days in young, healthy skin — and slows significantly as we age or when Vitamin A levels drop.

Vitamin A is the primary regulator of this process. It signals keratinocytes (the main cell type in the outer skin layer) to divide, differentiate, and shed at the right rate. Without adequate Vitamin A, cell turnover slows. Dead cells accumulate on the surface instead of shedding cleanly, leading to dullness, rough texture, clogged pores, and uneven tone.

Collagen Production

Collagen is the structural protein that gives skin its firmness and elasticity. It is produced by fibroblasts in the dermis — the deeper layer of skin beneath the epidermis — and Vitamin A is one of the primary signals that tells fibroblasts to keep producing it.

Vitamin A also inhibits the enzymes (matrix metalloproteinases, or MMPs) that break collagen down. So it works on both sides of the equation: stimulating production and slowing degradation. When Vitamin A is depleted, collagen production decreases and breakdown accelerates. The result is loss of firmness, the formation of fine lines, and skin that loses its ability to bounce back.

Barrier Function

The skin's barrier — the outermost layer of the epidermis — is responsible for keeping moisture in and environmental aggressors out. It is made up of tightly packed cells surrounded by lipids (fats), and its integrity depends on proper cell differentiation, which Vitamin A directly controls.

When Vitamin A levels are low, the barrier becomes compromised. Cells do not differentiate correctly, the lipid matrix becomes disorganized, and the barrier loses its ability to hold water effectively. The result is transepidermal water loss — skin that feels dry, tight, and reactive, and that is more vulnerable to irritants, allergens, and environmental damage.

Sebum Regulation

Vitamin A regulates the activity of sebaceous glands — the glands that produce oil (sebum) in the skin. Adequate Vitamin A keeps sebum production balanced. Deficiency can lead to either excess oil production (contributing to breakouts and congestion) or insufficient oil production (contributing to dryness and flakiness), depending on the individual.

Wound Healing and Repair

When the skin is damaged — whether from a cut, a breakout, sun exposure, or environmental stress — Vitamin A is essential to the repair process. It accelerates the migration of new cells into the wound site, stimulates collagen synthesis in the healing tissue, and helps regulate inflammation. Skin that is Vitamin A-deficient heals more slowly and is more likely to scar.

How UV Exposure Depletes Vitamin A

Here is the part that most people do not know: every time your skin is exposed to UV radiation, Vitamin A is destroyed.

This is not a gradual, long-term process. It happens immediately and measurably. Studies have shown that a single dose of UV radiation — equivalent to a day at the beach, or even a shorter period of unprotected sun exposure — can reduce the skin's Vitamin A content by up to 80 percent.

The mechanism is direct photodegradation. UV rays, particularly UVA (which penetrates deep into the dermis and is present year-round, even on cloudy days), break down retinoids in the skin through a process called oxidation. The Vitamin A molecules absorb UV energy and are chemically altered into inactive forms that the skin cannot use.

This means that for most people who spend any time outdoors — even incidentally, commuting or running errands — the skin is in a near-constant state of Vitamin A depletion. The body does not produce Vitamin A on its own; it must come from diet or topical application. And the rate of depletion from UV exposure far outpaces what most people can replenish through food alone.

Environmental Stressors and Oxidative Stress

UV radiation is the most significant source of Vitamin A depletion, but it is not the only one. Environmental pollution — particularly particulate matter, ozone, and nitrogen dioxide found in urban air — generates free radicals in the skin. Free radicals are unstable molecules that damage cellular structures, including the retinoids stored in skin cells.

This process is called oxidative stress, and it depletes not just Vitamin A but the full spectrum of antioxidants the skin relies on — including Vitamins C and E. The three work together: Vitamin C regenerates Vitamin E, and Vitamin E protects Vitamin A from oxidation. When one is depleted, the others become more vulnerable.

For anyone living in an urban environment, commuting in traffic, or simply spending time outdoors, oxidative stress is a daily reality. The skin is constantly fighting a battle against free radical damage, and Vitamin A is on the front line.

What Vitamin A Deficiency Looks Like

Because Vitamin A depletion is so common — and because it happens gradually — most people do not recognize it as a deficiency. They just think their skin is "aging" or "difficult." But the signs are consistent and recognizable once you know what to look for:

Rough, uneven texture. When cell turnover slows, dead cells accumulate on the surface. The skin feels rough to the touch and looks dull and uneven, even when well-moisturized.

Fine lines and loss of firmness. Reduced collagen production and accelerated breakdown show up as lines, particularly around the eyes and mouth, and a general loss of the skin's structural integrity.

Enlarged, congested pores. Slowed cell turnover means dead cells and sebum accumulate inside pores rather than shedding cleanly. Pores appear larger and are more prone to blackheads and congestion.

Persistent dryness and sensitivity. A compromised barrier cannot hold moisture effectively. The skin feels dry regardless of how much moisturizer is applied, and becomes reactive to products and environmental triggers it would otherwise tolerate.

Slow healing. Breakouts, minor wounds, and areas of irritation take longer to resolve. Post-inflammatory marks linger. The skin's repair capacity is visibly reduced.

Increased sun sensitivity. This is one of the less obvious signs. Vitamin A plays a role in the skin's ability to manage UV-induced damage. Depleted skin is more vulnerable to sunburn and more likely to develop hyperpigmentation after sun exposure.

Why Topical Replenishment Matters

Dietary Vitamin A — found in foods like liver, eggs, dairy, and orange and yellow vegetables — contributes to overall skin health, but it is not sufficient to counteract the rate of topical depletion caused by UV exposure and environmental stress. The skin needs Vitamin A delivered directly, at the site where it is being depleted.

This is the core principle behind Environ Skin Care, developed by Dr. Des Fernandes. His research showed that consistent topical application of Vitamin A — in the form of retinyl palmitate, which the skin converts into active retinoic acid at its own rate — could restore and maintain the skin's Vitamin A levels over time, reversing the signs of depletion and supporting the skin's fundamental ability to function.

The key word is consistent. Because UV exposure depletes Vitamin A daily, replenishment needs to be daily as well. It is not a treatment you do once and benefit from indefinitely. It is maintenance — the same way you eat every day because your body uses nutrients continuously.

---

Ready to start replenishing your Vitamin A? Kate carries a curated selection of Environ products — formulated specifically around the step-up system Dr. Des Fernandes developed. Browse the full range at Celtic Spa Skincare and find the right starting point for your skin.

---

The Takeaway

Vitamin A is not a skincare trend. It is the nutrient your skin is most dependent on and most consistently depleted of. The combination of daily UV exposure, environmental pollution, and the skin's own metabolic demands means that most people are operating with chronically low Vitamin A levels — and the skin shows it.

Replenishing it consistently, through a well-formulated topical product, is one of the most evidence-based things you can do for your skin's long-term health.

If you would like to know where to start, we are happy to walk you through it at your next appointment. Book online or reach out — we will assess your skin and recommend the right starting point for your Environ journey. See our advanced facial treatments to learn more.