Healthy blood is red. This is due to the presence of hemoglobin, a protein found in red blood cells that binds to oxygen. Hemoglobin is responsible for carrying oxygen from the lungs to the rest of the body and then returning carbon dioxide from the body to the lungs. The interaction between hemoglobin and oxygen gives blood its red color.
While it's true that deoxygenated blood appears darker, it's not blue. Blood remains red throughout the body, although the shade may vary depending on oxygen levels.
