Just when you thought that you had covered all your skincare acids, another buzzy, new one comes into the spotlight. We’re talking about lactobionic acid, an oxidised form of lactose and a polyhydroxy acid that doesn’t just exfoliate, but also acts as a humectant, too. Due to its larger molecular size, it doesn't penetrate the skin too well, making it a great choice for those with sensitive skin looking for surface-level exfoliation. Plus, some research indicates that this active can increase epidermal thickness as well. Say hello to healthy, hydrated skin! Pro tip: Even though this is a gentler acid, it’s best to start with a lower concentration of it in your skincare formulas and then build up slowly to avoid any negative reactions.