49 jaundiced, nonimmunized newborn infants with a birth weight of more than 2,000 g were given phototherapy with white light for more than 36 h. The average period of treatment was 61 h. 24 infants received 250 mg agar at the beginning of each meal at 3-hour intervals during phototherapy. 25 infants received phototherapy only. Serum bilirubin levels were decreased similarly in both groups. It is concluded that ingestion of agar does not supplement the effect of phototherapy.