Our daily bread. (IMAGE) University of Tokyo Caption There are more than 1,500 known types of yeast. Some are essential for baking and brewing, while others can cause infections which affect human and animal health. Credit 2022 Rohan Mehra Usage Restrictions Credit must be given to the creator. License CC BY Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.