The oldest skin-healing ingredient is up to some impressive new tricks If someone were to tell you that honey was the hottest ingredient in skin care, you might think, How nice, but I don’t shop at the Renaissance Faire. Honey seems to belong with beef tallow, egg yolks, oatmeal, apple-cider vinegar, and milk—soothing, innocuous foodstuffs re-purposed as face, body, and hair treatments that have been around since the dawn of time. Leave them to the historians and the food co-op.