Glycolic Acid (AHA): Surface Exfoliation Done Right

Glycolic acid is the smallest and most researched alpha hydroxy acid (AHA). It dissolves the bonds between dead skin cells on the surface, allowing them to shed faster. The result: smoother texture, brighter skin, and improved absorption of other products. When used correctly, it's one of the best ingredients for dull, rough-textured skin.

When used incorrectly, it strips your barrier and makes pigmentation worse. Here's how to get it right.

AHA vs BHA: the fundamental difference

This distinction matters because it determines which one you should use.

Glycolic acid (AHA) is water-soluble. It works on the skin's surface, dissolving the "glue" between dead cells. It cannot penetrate into pores. Best for: dullness, rough texture, surface pigmentation, fine lines.

Salicylic acid (BHA) is oil-soluble. It can penetrate through sebum and get inside pores to dissolve clogs. Best for: blackheads, whiteheads, oily and acne-prone skin.

If your skin is oily and congested, BHA is your exfoliant. If your skin is dull, rough, and you want a "glow," AHA is your exfoliant. Using both on the same night is a fast track to a damaged barrier.

Concentrations: what actually works

Not all glycolic products are the same. Concentration and pH both matter.

5-10% leave-on products are the effective OTC range. At this concentration, applied 2-3 times per week, glycolic exfoliates enough to improve texture and brightness without excessive irritation. The Ordinary's Glycolic Acid 7% Toning Solution is the most searched glycolic product in India, and it sits right in this range.

Up to 30% professional peels should only be done by a dermatologist or trained professional. At-home peels above 20% are risky, especially on melanin-rich Indian skin where over-exfoliation triggers post-inflammatory hyperpigmentation. A badly done peel on Fitzpatrick IV-V skin can leave marks that take months to fade.

pH matters as much as percentage. Glycolic acid needs a low pH (around 3-4) to be effective. A 10% glycolic at pH 5 will exfoliate less than a 7% glycolic at pH 3.5. Most reputable brands formulate within the effective pH range, but cheap or poorly made products sometimes don't.

Low-concentration glycolic in cleansers (1-3%) does very little. The contact time is too short for meaningful exfoliation. If your only glycolic product is a face wash, you're not getting the exfoliation benefit. A leave-on product (toner, serum, or pad) at 5-10% is what you need.

Sunscreen is non-negotiable

This isn't optional advice. It's the mechanism of the ingredient. Glycolic removes the top layer of dead cells, which serves as a (minor) natural UV shield. Without that layer, UV penetrates more easily. Without daily broad-spectrum sunscreen (SPF 30+), every benefit of glycolic is reversed by sun damage.

Apply glycolic at night. Apply sunscreen every morning. If you're not willing to commit to daily sunscreen, do not use glycolic acid.

How things go wrong

Glycolic is one of the easiest actives to misuse, and the consequences on Indian skin are visible.

Over-exfoliating. Using glycolic nightly from day one, or using it alongside retinol and BHA. Your barrier gets compromised: redness, peeling, stinging when applying moisturiser, skin that looks "shiny" but not in a good way. The fix: start twice a week, increase slowly, never combine with other exfoliants on the same night.

Using glycolic without sunscreen. This is the most common mistake and the most damaging one. You're increasing cell turnover and UV sensitivity simultaneously. The dark spots you're trying to fade get darker. The "brightening" effect reverses into a worsening of pigmentation. This is why many people say "glycolic made my skin darker." It wasn't the glycolic. It was the missing sunscreen.

Using it on irritated or compromised skin. If your barrier is already damaged (from over-exfoliating, retinol irritation, or eczema), adding glycolic makes everything worse. Fix your barrier first with ceramides and gentle moisturisers for 2-4 weeks, then reintroduce glycolic slowly.

At-home high-concentration peels. 20-30% glycolic peels purchased online without professional guidance. On darker skin tones, the risk of chemical burns and severe PIH is real. These should only be applied by someone who understands your skin type, can assess tolerance, and knows when to neutralise.

The Ordinary's 7% Toning Solution

This product is worth addressing specifically because it dominates Indian search queries for glycolic acid. At ₹850-950 for 240ml, it's one of the most cost-effective glycolic products available.

It's a good product at a good concentration. The large bottle lasts months because you use it sparingly. Apply with a cotton pad on clean, dry skin, 2-3 times per week at night. Follow with moisturiser. Use sunscreen the next morning.

Where people mess up: using it every night because the bottle is huge and it's "just a toner." It's not a hydrating toner. It's an exfoliating acid. Treat it like an active, not like water.

How to start safely

• Begin with 5-7% glycolic, twice a week, at night only.
• Apply on clean, dry skin (not damp, unlike HA). Wait 1-2 minutes before moisturiser.
• Use sunscreen every single morning. SPF 30+ minimum.
• After 3-4 weeks, if tolerated well, increase to every other night.
• Do not combine with retinol, BHA, or benzoyl peroxide on the same night.
• If you experience persistent redness, stinging, or peeling, scale back. Your barrier is telling you it's too much.

Common questions

How often should I use glycolic acid?

Start with twice a week, at night. If your skin tolerates it well after 2-3 weeks (no persistent redness, peeling, or stinging), you can increase to every other night. Most people should not use it nightly. If your skin feels tight, looks shiny-red, or stings when you apply moisturiser, you're using it too often. Scale back.

Can glycolic acid remove dark spots?

It can help fade surface-level pigmentation by speeding up cell turnover, removing the pigmented dead cells faster. But it won't address deeper pigmentation like melasma. For dark spots from acne (PIH), glycolic helps modestly. Niacinamide and azelaic acid have stronger evidence for Indian skin pigmentation. And critically: glycolic without sunscreen will make dark spots darker because of the increased sun sensitivity.

Glycolic acid vs salicylic acid: which one should I use?

They do different things. Glycolic (AHA) is water-soluble and works on the skin surface. Best for dullness, texture, and surface pigmentation. Salicylic (BHA) is oil-soluble and penetrates inside pores. Best for blackheads, whiteheads, and oily/acne-prone skin. If your main concern is acne and clogged pores, use salicylic. If your concern is dullness and rough texture, use glycolic. Do not use both on the same night.

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