CSPI is a non-profit health-advocacy group based in Washington, D.C., that focuses on nutrition and food safety.  CSPI provides valuable, objective information to the public, represents citizens' interests before governmental bodies, and serves as a watchdog over industry.  CSPI publishes Nutrition Action Healthletter (NAH), the nation's largest‑circulation nutrition newsletter.  CSPI is supported by the subscribers to NAH, donors, and foundation grants.