Sarmiento writes for MindaNews, where he has been a reporter since 2003. He also contributes articles to various publications including Business World, Sunstar Davao, Asia Times Online, The Mindanao Cross, and the Union of Catholic Asian News. For his exemplary reporting, Sarmiento has received awards including the Pagkilalasamga Natatanging Kuwentong Katutubo (Outstanding Story on Indigenous People – Broadsheet Category) given by the International Labor Organization (ILO) in 2011. He was also one of the top 10 finalists of the first Gawad Galing for Biotech Journalism, and the Biotechnology for Life Media and Advocacy Resource Center, both in 2005.