Researchers have found that people with bloodshot eyes are considered sadder, unhealthier and less attractive than people whose eye whites are untinted

Bloodshot eyes occur when the small blood vessels of the usually transparent conjunctiva membrane on the surface of the eye become enlarged and congested with blood, giving a red tint to the underlying sclera, the "white" of the eyes. Redness of the sclera is believed to be a general but important sign of a person's emotional and biological state.