Many sufferers complain of a continuous metallic taste in their mouth. This is from the iron in the blood which produces the metallic taste. With the blood loss, the breath can become worse. First it'll have an iron or metallic smell and then change into a more foul scent as the blood decomposes. While checking for bad breath, check to see if there's inflammation of the gums and blood. This will be a good indicator that the bad breath is due to gum disease.