Acids for the Face: AHA, BHA, PHA — Which to Choose and How to Use

Acids for the face are one of the most effective skincare tools: they exfoliate, even out tone, clean pores, and fight acne. But they are also the ones people most often "burn" their skin with due to the wrong concentration and frequency. Let's break down how AHA, BHA, and PHA differ, which acid to choose for your skin, and how to use acids without harm.

What Acids for the Face Are

Exfoliating acids dissolve the "glue" between dead cells of the stratum corneum, speeding up skin renewal. The result is smoother, more even, glowing skin with fewer comedones and less pigmentation. Unlike scrubs, this is chemical exfoliation — gentler and more even, without microtrauma.

AHA, BHA and PHA — the Difference

• AHA (alpha-hydroxy acids) — water-soluble, work on the surface. Glycolic, lactic, mandelic. Good for dull skin, texture, and pigmentation.
• BHA (beta-hydroxy acid, salicylic) — oil-soluble, penetrates pores. Ideal for oily skin, blackheads, and acne; see blackheads and enlarged pores.
• PHA (polyhydroxy acids) — gluconolactone, lactobionic. The gentlest, for sensitive skin.

Which Acid Suits Whom

To choose an acid, go by your skin type and goal:

• Oily skin, pores, acne → BHA (salicylic)
• Dull skin, fine lines, uneven tone → AHA (glycolic)
• Dry or sensitive skin → lactic acid or PHA
• Pigmentation → AHA + sun protection (plus actives from niacinamide: what it is for)

Concentration and pH of Acids — Why It Matters

The effect depends not only on the percentage but on pH (acidity): home products are usually 5–10% AHA or 0.5–2% BHA at a pH around 3–4. Professional peels are higher and under specialist supervision. A high percentage at home without experience = a risk of burns and post-inflammatory pigmentation. How to assess composition and active concentration is in how to check cosmetics ingredients.

How to Use Acids and Not Burn Your Skin

• Start 1–2 times a week in the evening, gradually increasing
• Don't mix many actives at once (acids + retinol + scrub = overkill)
• Don't use on damaged or irritated skin
• With burning, persistent redness, or flaking — take a break
• Introduce one product at a time to understand the reaction

Acids and the Sun: Why SPF

Acids increase skin sensitivity to UV, so daily SPF is mandatory while using them — otherwise you may get pigmentation instead of an even tone. AHA is better applied in the evening. This rule is especially important if the goal is to lighten dark spots on the face.

Myths About Acids

• "Acids thin the skin" — on the contrary, in moderate doses they stimulate renewal and collagen synthesis
• "The more it stings, the better it works" — stinging is a sign of overkill, not effectiveness
• "Acids are only for problem skin" — gentle AHA/PHA are useful for normal skin care too

Matching an acid and concentration to your skin is helped by cosmetics matching by composition.

This information is for educational purposes and does not replace a specialist consultation.