Nathan & Sons, trading as Underbrush, is a US-based company that creates natural, functional gum products. Founded in 2022 by Nathan, the company developed a gum that supports oral health using natural ingredients like hydroxyapatite, minerals, and xylitol. Underbrush gum is made with a unique natural gum base sourced from around the world, including mastic gum, spruce gum, and chicle gum. The result is a product that polishes teeth, supports remineralization, and freshens breath without synthetic chemicals or plastics.