10. Renal Failure
A common result of kidney disease and failure is a metallic taste in the mouth. When the kidneys are not functioning optimally, toxins and waste products build up in the blood. This is called uremia and can result in bad breath, loss of appetite and a metallic taste in the mouth. Causes of uremia include, among others, diabetes, hepatitis B, heart disease, cancer and kidney stones. Interestingly, high protein diets have also been implicated in kidney damage and subsequent uremia. Uremia can be reversed if treated quickly, but permanent damage to the kidneys can result if it is left untreated for an extended period of time.