Triple Acid Power: AHA, BHA, and PHA Blend That Transforms Sensitive Skin

Photoaging—caused by prolonged sun exposure—leaves behind telltale signs like wrinkles, uneven skin tone, hyperpigmentation, and dryness. While exfoliants are often used to address these issues, people with sensitive skin frequently find them too harsh. A recent clinical study published in the Journal of Cosmetic Dermatology explores the use of a novel 12% triple-acid exfoliating serum, combining AHA (alpha hydroxy acid), BHA (beta hydroxy acid), and PHA (polyhydroxy acid), designed specifically for sensitive, photoaged skin.

Let’s explore the science, results, and real-world impact of this powerful yet gentle formulation.

Chemical exfoliants like AHA, BHA, and PHA are commonly found in skincare products—but each works differently and targets unique skin concerns:

• AHA (Alpha Hydroxy Acid): Glycolic acid, a small hydrophilic AHA, increases epidermal thickness, boosts collagen production, and elevates hyaluronic acid levels in skin, promoting hydration and reducing wrinkles. Studies show it stimulates collagen synthesis and epidermal renewal without triggering inflammation.
• BHA (Beta Hydroxy Acid): Salicylic acid is oil-soluble and excellent for acne-prone or oily skin. It is structurally related to aspirin and helps reduce redness and acne, acting as a keratolytic agent that removes dead cells by breaking down intercellular glue.
• PHA (Polyhydroxy Acid): Known for their gentle exfoliation and antioxidant benefits, PHAs like lactobionic acid and gluconolactone are ideal for sensitive skin. Lactobionic acid not only enhances moisture but also prevents oxidative damage and inhibits enzymes that degrade collagen.

Combining all three creates a synergistic effect: deep exfoliation without irritation, even for skin that is typically reactive or delicate.

The study assessed DWB-EN, a 12% triple-acid serum created by Dr. Whitney Bowe Beauty, and tested it over 4 weeks on 30 women aged 35–60 with signs of mild to moderate photoaging, including:

• Wrinkles
• Sun damage
• Uneven skin tone
• Hyperpigmentation
• Enlarged pores

Application Protocol:

• Use: Three times a week at night on clean skin
• Duration: 4 weeks
• Exclusion criteria: Recent use of retinoids, laser treatment, or skin conditions like eczema
• Washout period: 7 days with standardized cleanser only

The serum also included aloe vera, sea buckthorn oil, resveratrol, and post-biotics, which were designed to counterbalance the acid strength and support skin barrier function.

The results were compelling—both instrumental assessments and clinical grading showed statistically significant improvements across all categories. Let's break them down:

1. Skin Hydration Skyrocketed by 175%

Using a corneometer (a device that measures moisture through electrical capacitance), hydration increased:

• 123% overnight
• 161% by week 2
• 175% by week 4 (p < 0.001)

This dramatic hydration improvement supports the benefits of glycolic acid and PHAs as humectants (ingredients that draw moisture to the skin).

2. Skin Luminosity Increased by 4.36%

Measured using a colorimeter, which assesses light reflection on the skin:

• 2.09% overnight
• 3.36% at week 2
• 4.36% at week 4 (p < 0.001)

Even this small percentage made a noticeable difference in how radiant and youthful the skin appeared.

Subjective self-assessments echoed the clinical findings:

• 93% felt their skin looked more radiant after one use
• 96% said their skin felt softer and more hydrated after one night
• 100% agreed that after 4 weeks, their skin was firmer, brighter, and more youthful

This is particularly impressive because 50% of subjects had sensitive skin, yet no irritation or adverse effects were reported.

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AHA, BHA, and PHA—Safe for Sensitive Skin

Concerns about exfoliation triggering sensitive skin flare-ups are common. But this study directly addresses that.

A Human Repeat Insult Patch Test (HRIPT) with 56 participants showed no irritation or sensitization, even during the challenge phase, which is designed to detect potential allergic reactions.

Even among individuals with self-reported sensitive skin, zero cases of dryness or redness occurred throughout the study period.

This result validates that, when formulated carefully with barrier-supportive ingredients, a high-strength exfoliating acid blend can be both safe and effective for sensitive skin.

The success of this formula isn’t just about combining three acids. It’s about formulation strategy, which includes:

• Glycolic acid (AHA) to stimulate collagen and epidermal renewal
• Salicylic acid (BHA) for oil control and anti-inflammatory action
• Lactobionic acid and gluconolactone (PHAs) for gentle exfoliation and antioxidant protection
• Sea buckthorn oil, aloe vera, and resveratrol to support the skin barrier

The synergy between exfoliation and hydration ensures the skin doesn’t just look better—it functions better.

This 4-week clinical trial confirms what cosmetic dermatologists have long suspected—a synergistic blend of AHA, BHA, and PHA can transform even sensitive, photoaged skin when paired with supporting ingredients.

Key benefits backed by data:

• Hydration: +175%
• Radiance: +79.59%
• Texture: +127%
• Hyperpigmentation: +86.41%
• Wrinkle reduction: +35%
• Zero irritation: 100% tolerability in sensitive skin

With consistent use and careful formulation, triple-acid exfoliants are no longer limited to those with resilient skin types. This opens the door for more inclusive, results-driven skincare routines for users of all backgrounds.