WHEN USED CORRECTLY, EXFOLIATING ACIDS ARE HIGHLY EFFECTIVE AT IMPROVING SKIN TEXTURE AND RADIANCE AND PREVENTING ACNE
If you have a dull complexion, clogged pores, wrinkles, or blemishes, exfoliation can be your best beauty ally. But between AHAs, BHAs, PHAs, glycolic acid, salicylic acid, and all the other acids available in cosmetics, it is easy to feel lost. Which acid should you choose for your skin type? How often should you use it? How can you avoid the mistakes that can damage your skin?
This complete guide explains everything you need to know about exfoliating acids: how they really work, their key differences, how to choose them according to your skin and your goals, how to use them correctly in your routine, and above all the mistakes you absolutely need to avoid. Whether you are a complete beginner or already a skincare expert, you are about to discover how to deeply transform your skin through the science of exfoliating acids. When used correctly, exfoliating acids are remarkably effective at improving skin texture and radiance, preventing acne, reducing wrinkles, and refining pores. Get ready to reveal smoother, brighter, more radiant skin.
WHAT IS EXFOLIATION AND WHY IS IT ESSENTIAL?
Exfoliation consists of removing the dead skin cells that accumulate on the surface of the skin to reveal the fresh new cells underneath. It is the key to achieving a brighter, fresher, blemish-free complexion, and it also allows the skincare products that follow (serums, creams) to penetrate better.
Natural Cell Turnover
Every day, your skin renews itself naturally: surface cells die while new cells replace them from deeper layers. In adulthood, this complete cell turnover cycle takes about 30 days. Your cells gradually rise from the dermis to the epidermis where they die and shed.
The problem: With age, this process slows down considerably. At 40, renewal can take as long as 45 to 60 days. The result: dead skin cells accumulate on the surface, leading to a dull complexion, a “thickened” appearance of the skin, clogged pores that encourage blemishes, and uneven texture.
The Benefits of Exfoliation
Regular, properly done exfoliation delivers spectacular results:
- Bright, radiant complexion: By removing the layer of dull dead cells, you reveal the fresh skin underneath, which reflects light better.
- Refined texture: The skin becomes visibly smoother to the touch, as if delicately “polished.”
- Unclogged and tightened pores: Exfoliation deeply cleans pores clogged with sebum and dead skin cells, helping prevent blackheads and breakouts.
- Better absorption of skincare: On exfoliated skin, your serums and creams penetrate up to 3 times better, maximizing their effectiveness.
- Collagen stimulation: Exfoliating acids send a signal to fibroblasts to produce more collagen, improving firmness and elasticity.
- Reduction of fine lines and wrinkles: By stimulating cell turnover and collagen production, exfoliation softens signs of aging.
- More even complexion: Reduction of pigmentation spots, acne scars, and hyperpigmentation.
- More even makeup application: On perfectly smooth skin, foundation applies flawlessly without a “crocodile skin” effect.
THE DIFFERENCE BETWEEN THE DIFFERENT AHA, BHA, AND PHA ACIDS
AHA ACIDS (Alpha Hydroxy Acids)
AHAs are water-soluble and work mainly by exfoliating the surface of the skin to make it more radiant by brightening the complexion and improving texture. They also stimulate hydration and promote collagen production.
Choose an AHA if you want to treat fine lines, even out your skin tone and texture, or if you have oily skin.
THE DIFFERENT AHAs
GLYCOLIC ACID
Glycolic acid is the acid that penetrates deepest into the skin, so it is the most effective because it has the smallest molecule of all the acids. It can dissolve excess sebum and dead skin cells, revealing smoother, brighter, younger-looking skin.
It regenerates collagen and reduces the appearance of fine lines and wrinkles. It reduces dark spots and scars. It is recommended for preventing acne and blackheads by unclogging pores. It is not recommended for sensitive skin but can be used by pregnant women.
LACTIC ACID
Lactic acid is the second smallest molecule after glycolic acid. It is a good alternative for sensitive skin because it delivers the same results as glycolic acid while being very gentle and well tolerated by all skin types. This acid, derived from sugar or fermented milk, improves skin texture and radiance. In addition, it is a humectant that attracts water.
Our Lactic Acid skincare:
• Holi (Bright) Resurface Glass Face Mask - AGENT NATEUR
• Flower Acid Algae Serum - MARA
FRUIT ACIDS
Fruit acids are the gentlest. These include citric acid and malic acid. Their molecules are larger and therefore act on the upper layer of the skin. They are often combined with glycolic or lactic acids to boost their effectiveness.
Our Fruit Acid skincare:
• Synergie[4] 4-in-1 Powder Mask Probiotic + Fruit Acids - ODACITE
• Algae and Enzyme Cleansing Oil - MARA
BHA ACIDS (Salicylic Acid)
Salicylic acid is one of the most popular ingredients for treating acne. It penetrates and dissolves the sebum clogging pores while exfoliating dead skin cells. Better still, it works without irritating already inflamed skin because it has anti-inflammatory properties. If you have never used an acid before, salicylic acid is perfect for getting started.
Originally, salicylic acid or BHA is extracted from willow bark, from which it gets its name, but it is also present in many fruits and vegetables such as almonds, tomatoes, apricots, grapes... It is mainly known for its pain-relieving and anti-inflammatory properties but also offers many other benefits for the skin. It is one of the most popular ingredients for treating acne, blackheads, and enlarged pores.
The benefits of salicylic acid:
REDUCES BLEMISHES AND HELPS PREVENT THEM
Salicylic acid gently exfoliates the skin by penetrating pores and dissolving sebum, impurities, and bacteria that clog them, while also exfoliating dead skin cells. By cleansing the pores, it helps prevent blemishes from forming.
REDUCES THE APPEARANCE OF PIGMENTATION SPOTS
Sun exposure can cause pigmentation spots to appear. Using BHA-based skincare helps eliminate dead skin cells and brighten the complexion thanks to its exfoliating properties. This also stimulates cell turnover.
REDUCES INFLAMMATION
Salicylic acid also has anti-inflammatory and antimicrobial properties that can help reduce inflammation, redness, and itching resulting from sun exposure.
KEEPS THE SKIN RADIANT AND NON-GREASY
BHAs help improve skin texture and radiance, which tends to become duller during summer. Skin also tends to get shinier more easily, which is why it is useful to use a cleanser or toner to counter excess sebum production and reduce pore size.
A very important point is that salicylic acid does not increase the skin’s sensitivity to the sun, so it can be applied morning and evening to deeply cleanse the pores. We still recommend following its application with sun protection.
Our Salicylic Acid skincare:
• Renewing Polish - Renovating Scrub - GRESSA SKIN
• Blue Aura Turmeric Micellar Water + Holy Basil - ODACITÉ
• Hydra-Purifying Treatment Mist Mint + Green Tea - ODACITÉ
• Daily Hydra Exfoliant White Tea + Rooibos and Jojoba Beads - ODACITÉ
PHA ACIDS (Polyhydroxy Acids)
PHAs represent the new generation of exfoliating acids, developed specifically for skin that cannot tolerate traditional AHAs or BHAs. Chemically, they are similar to AHAs (also water-soluble), but their molecular structure is radically different.
The major difference: PHAs have molecules that are much larger than traditional AHAs. While glycolic acid (AHA) measures 76 daltons, a PHA such as gluconolactone reaches 178 daltons. This large size completely changes the way they behave on the skin.
Consequence: PHAs penetrate much more slowly and superficially into the epidermis. They remain mainly on the surface of the skin, where they provide ultra-gentle exfoliation without ever reaching the deeper layers that are more prone to irritation. It is like getting exfoliating effectiveness without the aggression.
Another unique feature: PHAs contain multiple hydroxyl groups in their chemical structure, giving them hydrating and antioxidant properties that other acids do not possess to the same degree.
HOW TO USE: HOW TO USE ACIDS CORRECTLY
Frequency of Use
BEGINNER:
Week 1-2: 1x/week
Week 3-4: 2x/week
Month 2: 3x/week if well tolerated
ACCUSTOMED SKIN:
3x/week or daily in a cleanser
GOLDEN RULE: Increase gradually. It is better to underdo it than overdo it.
Time of Application
Always in the evening
In the morning, the skin has just finished its overnight regeneration work: this is when it naturally repairs and strengthens its skin barrier, that thin protective layer that retains hydration and blocks external aggressors.
Applying acids upon waking means weakening this freshly rebuilt barrier. The result: the skin becomes more vulnerable to dehydration, bacteria, and blemishes. Worse still, when exposed to the sun, it may react more intensely to UV rays and lose its balance.
Reserve acids for the evening. That is when the skin is most receptive to cell renewal and can fully benefit from their effects, without interfering with its natural defense mechanisms.
Also, in the evening, you do not put makeup on afterward, which leaves the skin completely free to breathe and regenerate without interference.
Order in the Routine
COMPLETE EVENING ROUTINE:
1. DOUBLE CLEANSING: Makeup-removing oil + Cleanser
→ Removes makeup, sebum, impurities
2. TONER
→ Rebalances pH after cleansing. Maximizes absorption of the skincare that follows
3. EXFOLIATING ACID (AHA/BHA/PHA)
→ ON CLEAN, DRY SKIN (important!)
→ Apply all over the face (avoid the eye contour)
→ WAIT 1-2 MINUTES before the next step to allow the product to penetrate properly
4. TARGETED SERUM (hydration, anti-aging...)
→ Hyaluronic acid, niacinamide, peptides
5. EYE CONTOUR CARE
6. FACE OIL
→ Applying an oil as the final step of the routine helps seal in hydration and boost the effectiveness of the skincare applied underneath. Thanks to its slightly occlusive effect, the oil forms a protective film that prevents water from evaporating and keeps the active ingredients where they need to work: deep within the skin.
Good pairings
Skin cycling is an intelligent nighttime method that alternates the application of powerful actives (acids, retinol) with restorative rest phases for the skin.
Instead of layering many different products that can compromise the skin barrier, this technique relies on a three-night cycle:
Day 1: exfoliation with exfoliating acids, to remove dead skin cells and smooth skin texture.
Day 2: application of a retinol-based treatment, to stimulate cell renewal and collagen production.
Day 3: recovery phase, where restorative and hydrating skincare is prioritized to allow the skin barrier to regenerate.
This method optimizes the effectiveness of each product without weakening the skin, while respecting its natural regeneration rhythm.
Skin Cycling puts back at the center what the skin truly needs: rhythm, breathing space, and respect. By following this pace, you achieve healthier, brighter, stronger, more resilient skin — skin that progresses without ever being aggressed.