Inflation is for egg prices, not active ingredients. And yet, we are witnessing huge inflation in active ingredient concentration in skincare. Take vitamin C, once used at 10 percent, now commonly formulated at 20 percent. Niacinamide, whose recommended use level is 2 to 5 percent, is increasingly used at 10 percent. Even the concentration of the mighty (and mighty aggressive) retinol is inflated. 1 percent is the upper limit for daily retinol, but it is now available at 2.5 percent for the face; no prescription required. Is this what product development has come to—brands attempting to outdo each other by ratcheting up their active ingredient concentrations?The runaway inflation train must stop! When it comes to the concentration of active ingredients, more is not better. In fact, it is frequently worse. Using too much retinol, for example, can lead to skin irritation, disruption of the skin barrier, flaking, peeling, redness (“retinol burn”), sun sensitivity, and even vitamin A toxicity. Active ingredients have targeted concentration ranges for a necessary purpose: because that is what is safe and efficacious. You wouldn’t take 2000 mg of ibuprofen, so why do this to your skin?Indeed, recent EU regulation has restricted the concentration of retinol for over-the-counter products to just 0.3 percent in face products, and 0.05 percent in body products. Kojic acid has also been reined in. Earlier this year, the EU restricted the use of this skin brightening and lightening ingredient to a maximum of 1 percent in face and hand products.