Glycolic Acid

Glycolic acid is the smallest alpha-hydroxy acid (AHA), which means it penetrates skin more deeply and effectively than any other acid in its class. Derived from sugarcane, it has the most extensive clinical research behind it of any chemical exfoliant — decades of studies supporting its ability to improve skin texture, fade dark marks, reduce fine lines, brighten uneven tone, and unclog pores. It works by dissolving the bonds that hold dead skin cells together on the surface, accelerating the natural cell turnover process that slows with age. The result is smoother, brighter, more even skin - alongside a reduction in post-acne marks, sun-induced pigmentation, and early signs of ageing. Glycolic acid is best used in the evening, two to three times per week. It is most suited to resilient skin types comfortable with actives. Those new to acid exfoliation, or those with sensitive or darker skin tones, typically achieve better results starting with lactic or mandelic acid first. Start low, go slow, and always use SPF50 the following morning. Glycolic Acid FAQs How often should I use glycolic acid? Start with two to three times per week in the evening and increase frequency over four to six weeks as your skin adjusts. Once acclimatised, some people use glycolic acid every other night. Avoid daily use unless your skin has been using acids consistently for several months - overuse damages the skin barrier and causes increased sensitivity rather than faster results. Can glycolic acid be used on the body? Yes - glycolic acid is highly effective on the body for keratosis pilaris (chicken skin on the upper arms), rough elbows and knees, body acne, and uneven body skin tone. Body skin is thicker and more resilient than facial skin, making it well suited to higher concentrations. Fundamentals Skincare formulates dedicated body exfoliants combining glycolic and salicylic acid for body use. Is glycolic acid safe for darker skin tones? Glycolic acid can be used by all skin tones but requires more caution with darker complexions. Its deep penetration increases the risk of triggering post-inflammatory hyperpigmentation if overused or applied to irritated skin. Start at a lower concentration, use no more than twice weekly, and never apply to compromised skin. Mandelic acid is a safer starting point for PIH-prone skin types. Can I use glycolic acid with retinol or vitamin C? Do not use glycolic acid on the same night as retinol - the combination increases irritation without additional benefit. Vitamin C (L-ascorbic acid) is also best kept separate. Instead, alternate: glycolic two to three nights per week, retinol on alternate nights. Glycolic pairs well with hyaluronic acid and niacinamide, which support the barrier during exfoliation. What is the difference between glycolic acid and salicylic acid? Glycolic acid is water-soluble and works on the skin surface - best for texture, brightness, fine lines, and dry skin exfoliation. Salicylic acid is oil-soluble and works inside the pore - best for blackheads, congestion, oiliness, and acne. For combined concerns, alternate on different nights. If you have oily or acne-prone skin, salicylic acid should be your primary exfoliant.