Lactic Acid in Skincare: Everything You Need to Know
May 18, 2025In the ever-expanding world of skincare, actives like Vitamin C, Retinol, and Niacinamide often steal the spotlight. But Lactic Acid—a dermatologist-loved Alpha Hydroxy Acid (AHA)—is a quiet powerhouse that deserves a place in your routine. Known for its gentle exfoliating action, hydration benefits, and barrier-supportive nature, Lactic Acid is one of the most researched and recommended ingredients for a wide range of skin types and concerns. This blog dives deep into the science behind Lactic Acid, how to use it, what to pair it with, and why it’s a gold standard in dermatology.
What is Lactic Acid?
Lactic Acid is an Alpha Hydroxy Acid (AHA). Its primary function is chemical exfoliation—it loosens the bonds between dead skin cells, encouraging their natural shedding to reveal a smoother, brighter complexion underneath. Due to its larger molecular size compared to Glycolic Acid, Lactic Acid penetrates more slowly, making it gentler and more suitable for sensitive skin.
How Does Lactic Acid Work?
Lactic Acid breaks down the desmosomes—or cellular glue—that binds dead skin cells together on the surface of the skin. This makes it a chemical exfoliant, as opposed to a physical one like scrubs or brushes. The exfoliation process also encourages cell turnover and helps with collagen stimulation. Beyond exfoliation, Lactic Acid is also a humectant, meaning it draws moisture into the skin, keeping it hydrated while treating issues like hyperpigmentation and fine lines.
Benefits of Lactic Acid
-
Gently exfoliates and refines skin texture
-
Promotes even skin tone by reducing pigmentation and melasma
-
Improves hydration due to its humectant properties
-
Supports collagen production and reduces signs of ageing
-
Improves skin’s radiance and luminosity
-
Helps reduce post-acne marks and scars
Who Should Use Lactic Acid?
Lactic Acid is safe and effective for all skin types—especially dry, dull, and sensitive skin. However, its versatility means it also benefits oily and acne-prone skin types when incorporated correctly.
Compatibility & Layering Guide
Lactic Acid works well with most hydrating and soothing ingredients such as Hyaluronic Acid, Ceramides, and Panthenol. However, it should not be mixed directly with other low-pH actives like Vitamin C (Ascorbic Acid), Retinol, or other AHAs/BHAs (e.g., Glycolic, Salicylic Acid) to avoid irritation. For sensitive skin, alternate these in AM/PM routines instead of layering.
Best Practices for Use
-
Frequency: Begin with 2-3 applications per week, gradually increasing as tolerated.
-
Sun Protection: Always use sunscreen daily, as AHAs like lactic acid can increase sun sensitivity.
-
Application: Apply to clean, dry skin at night.
-
Hydration: Follow with a moisturiser to lock in hydration.
Can Lactic Acid Cause Purging?
Yes, like other exfoliants, Lactic acid can accelerate skin cell turnover, which may lead to temporary breakouts (purging). This is a normal part of the process and usually clears up within 1-2 weeks. If breakouts persist beyond this timeframe, consider reducing frequency or discontinue use.
Lactic Acid Compared To Other Acids
-
Glycolic Acid: Known for its potency, glycolic acid has a smaller molecular size, which allows for deeper penetration but may also increase the risk of irritation.
-
Salicylic Acid (BHA): This oil-soluble acid is particularly effective for oily and acne-prone skin, helping to unclog pores and reduce breakouts.
-
Mandelic Acid: A gentle exfoliant, mandelic acid is ideal for those with very sensitive skin, providing effective results without causing irritation.
-
Azelaic Acid: Renowned for its dual action, azelaic acid effectively targets inflammation and hyperpigmentation, making it perfect for individuals with rosacea or acne-prone skin.
Who Should Avoid Lactic Acid?
Compromised Skin Barriers: Individuals with severely compromised skin barriers, such as those with eczema or open wounds, should refrain from using lactic acid until their skin has fully healed.
Milk Allergies: Those with a known allergy to milk should avoid lactic acid, given its dairy origin, and consult a dermatologist for alternatives.
Sensitivity to AHAs: If you have a history of sensitivity or adverse reactions to alpha hydroxy acids (AHAs), it is advisable to consult a dermatologist before using lactic acid.
FAQs
Q: Can I use Lactic Acid every day?
A: Yes, if the concentration is low (under 5%). Otherwise, limit to 2–3 times per week.
Q: Is Lactic Acid safe during pregnancy?
A: Generally yes, but always consult your OB-GYN first.
Q: Can I use it with Niacinamide?
A: Yes. Lactic Acid exfoliates, while Niacinamide soothes and balances skin tone.
Juicy Chemistry’s Lactic Acid Toner
Our 5% Lactic Acid Exfoliating Toner is thoughtfully formulated with Rose Hydrosol, Aloe Vera, and Hyaluronic Acid to deliver gentle exfoliation, hydration, and glow. It’s ideal for all skin types and helps address pigmentation, dullness, and texture without irritation. Dermatologically tested, COSMOS-certified organic, and clinically backed - this toner delivers efficacy with integrity.
Researches:
https://pmc.ncbi.nlm.nih.gov/articles/PMC11055559/
https://www.mdpi.com/1420-3049/23/4/863
https://www.mdpi.com/2072-6643/15/14/3123
https://www.fda.gov/cosmetics/cosmetic-ingredients/alpha-hydroxy-acids
