Pamela Marshall, clinical aesthetician and founder of Mortar & Milk clinic in London, agrees that retinol is a good ingredient to try during lockdown, but adds that it doesn't suit all skin types. "In fact, most people overuse it," she says. If your skin is congested, perhaps try exfoliating acids such as glycolic and lactic acid instead. They also make skin sensitive to sunlight, so Marshall's advice is to treat them the same as retinol and not overdo it. If your skin is on the more sensitive side, polyhydroxy acids (PHAs) may be a better solution, as they provide similar results over time but don't penetrate the skin as deeply. "PHAs are much gentler on the skin but still very active, and while they do exfoliate, they also hydrate and reduce inflammation," Marshall explains. SPF is a must during the day, no matter which acid you choose.