A structure on the tongue a taste bud contains taste buds (pink) that send information to the brain through taste nerve fibers (yellow). Each taste bud of cells that responds to specific sweet, bitter, umami, salty, sour or fatty tastes contains. Researchers are studying how taste buds are overwhelmed in adulthood. People who do not fully regenerate their taste buds due to cancer treatment, for example, may suffer from loss of appetite and malnutrition.