The acai palm tree, native to tropical Central and South America, produces a reddish-purple berry that is related to the blueberry and cranberry. Acai has become popular in the United States, where it has been promoted as a “superfood.” It is widely consumed as an edible fruit or as a juice. Recently, the Federal Trade Commission announced it has asked federal courts to temporarily suspend a series of fake news Web sites that have been marketing acai berry weight-loss products. Acai berry products have been widely marketed for weight-loss and anti-aging purposes, but there is no definitive scientific evidence to support these claims. People who are using or are considering using natural products, including acai, should discuss this decision with their health care provider.