There are actually well over 100 reasons for that metallic taste in your mouth, a few of which are common, whereas many of which are rare. That metal-like taste in your tongue could mean anything from a dental problem, to diabetes, to the fact that you are pregnant, or it could mean nothing much at all, or something taking a drink of water might cure. The possibility it is a symptom of something serious is remote, but like many other symptoms, if it comes on suddenly and lingers on, you might do well to have it looked into. The medical term for this type of abnormal taste in the mouth is dysgeusia, which is a condition, not a disease or a disorder.
Not a Normal Taste – But Still a Taste
Your taste buds sense sweet, sour, salty, bitter, or umami. The latter taste sensation could be described as savory or meaty, and is commonly associated with Asian foods. None of these five basic sensations can be described as metallic. Experiencing a taste resembling somewhat that of a metal could be thought of as something having hijacked your taste buds so that they send the wrong message to the brain. If, as many believe, a metallic taste results from a galvanic reaction that has taken place in the oral cavity, then it would not be surprising that a gustatory receptor could send out signals that convince the brain that a metal is present. Foods can also taste cool, pungent, or spicy due to various chemical reactions they cause in the gustatory buds.
13 Common Causes of a Metallic Taste
There are a few common denominators in this list, but in most cases it is difficult to trace exactly what is causing the unusual taste. At the end of the list you will find one of the more common causes of all, the idiopathic, where the actual cause is unknown.
Medications Are a Leading Cause
Medications are the leading cause of experiencing that metal-like taste. This should not come as a surprise, since there are so many different chemicals and compounds, both organic and inorganic, which might be present in the medications you are taking. A medication in itself may not have a bad taste resembling that of a metal, but such taste will be experienced as a side effect or an after-effect. In fact, a medication taken by injection is just as apt to cause an unusual taste in the tongue as one that is taken orally. Indinavir (used to treat HIV), captopril (a blood pressure medication), and antibiotics such as tetracycline, clarithromycin, and metronidazole are all known to cause dysgeusia. Also included in this category are various drugs used in chemotherapy, anti-thyroid medications, and drugs used to treat glaucoma.
Gingivitis and Other Dental Issues
One of the more common causes of dysgeusia is bleeding from the gums, whether it is due to trauma, or to bleeding from gingivitis, a common dental disease. Blood can have a slightly flavor at times although it is most often described as tasting salty. In most healthy people, there is enough iron in their blood to leave behind an off-taste if the blood is coming from the gums. Another dental-related cause could be an amalgam filling, especially an older one in the process of breaking down. Many of these older amalgam fillings contain a very small amount of mercury. When such a filling begins to break down, mercury vapor can be released in the oral cavity, the result being a definite metallic taste. Fortunately, the amount of mercury vapor released is insignificant as far as your health is concerned. Amalgam fillings or not, the leading cause of dysgeusia is often due to nothing more than poor dental hygiene habits.
Dehydration and Dry Mouth
While dehydration and dry mouth are not always one and the same thing, either can adversely affect, or at least alter your sense of gustation. The symptom itself is rarely harmful unless, over the longer term it begins to affect your desire to eat. Dry mouth can have many causes, a number of which can be traced to systemic diseases. Whether dehydration or dry mouth is the case, taking in plenty of liquid is more often than not, a good solution. Even if disease is the root cause, drinking lots of water is usually much more beneficial than it is harmful.
If You’re Pregnant, You’ll Likely Experience the Taste
Dysgeusia is very common during pregnancy, especially so during the first trimester. Estrogen, as well as other hormones closely associated with a pregnancy, is believed to play a role, as the changes in hormone levels during the initial stages of a pregnancy carry with them a number of symptoms. It is a well-known fact that when pregnant, a woman often has a heightened, or altered sense of smell. Since smell and gustation are interconnected senses, it would seem to make sense that anything affecting the sense of smell would also affect one’s gustation. In any event, an off-taste in the mouth is a rather commonplace experience if you are pregnant.
To say that sinus problems will cause dysgeusia would be an over simplification, especially since sinus problems can be many and varied. There is little doubt, however, that what goes on in your sinus cavities often affects what goes on in the back of your mouth. Given that, plus the fact that a sinus condition will often affect your sense of smell, sinus problems can easily create a bad taste in your mouth, and that bad taste will sometimes be a metallic one.
Experiencing dysgeusia is a symptom that is associated with a number of different systemic diseases. In many instances it can be difficult to determine just what it is about a given disease that causes this type of taste. In the case of cancer, it all depends on what type of cancer it is, and where it is located. The side effects of chemotherapy and radiation therapy used in treating cancer are known to cause gustatory changes, including that metallic taste most of us are very familiar with.
Hyperparathyroidism is closely associated with the calcium levels in the body as well as the levels of vitamin D. It is well known that a metallic off-taste is one of the symptoms of a vitamin D deficiency and of an excess of calcium in the bloodstream.
A somewhat common source of a metal taste is renal failure. Wastes in the blood tend to build up as the kidneys are no longer able to fully perform their intended function. This accumulation of wastes is called uremia. Uremia can cause bad breath and a loss of appetite because food no longer tastes appealing due to its awful taste. Diabetes is one of the many causes of renal failure, and a metal taste is one of the many symptoms of diabetes.
In the case of diabetes, the metallic off-taste is usually associated with a hypoglycemic, or low blood sugar, condition. It is in fact a rather common symptom and one that can sometimes serve as a warning. The metallic off-taste may or may not be caused by an outpouring of adrenalin, which will sometimes accompany a low sugar level. Adrenalin will also cause certain gustatory sensations. Some call this taste one of extreme bitterness, while others refer to it as being metallic.
An Excess of Vitamin D
Vitamin D can be a direct cause of a metallic off-taste, is when you have too much of it in your system. Most of the vitamin D you get either comes from sunlight or from foods such as milk, that have been fortified with the vitamin. If you are for some reason not getting enough of the vitamin and are experiencing some of the symptoms of a deficiency, you may elect to take supplements. Older people often take vitamin D supplements, especially if they spend the majority of their time indoors. Taking too much vitamin D can be toxic however, and one of the symptoms of the toxicity is a metallic taste.
An overdose of vitamin B12 can cause an off-taste, as can zinc. Zinc is a vital nutrient that provides many benefits. One of these benefits is that it is essential in having a well-developed sense of taste and of smell. Ironically, if the zinc levels in the body are excessive, a person’s sense of taste can be adversely affected, including the experience of having a metallic off-taste in one’s mouth. One source lists over 90 potential causes of metallic taste, many of them due to either an excess or a deficiency of one type of nutrient or another. The instances of this particular side effect occurring due to the nutrients you eat varies so widely from person to person, that it is virtually impossible to attempt to rank the importance of these nutrients in terms of any problems they might cause.
Not all food poisoning episodes will cause you to feel like you’ve been chewing on someone’s coin collection, as the tastes you may experience will vary. The metallic off-taste occurs when the food happens to be fish, particularly spoiled fish, or a certain species of fish. Food poisoning in this case is either called scombroid fish poisoning or histamine fish poisoning. Fish flesh that has spoiled, or has begun to spoil, contains a high level of histamine, produced when bacteria begin to break down the flesh. The flesh will often take on what has been described as a peppery or metallic flavor. The body reacts to eating the spoiled flesh much as it does to an allergen. Symptoms vary from person to person.
There are a number of different allergens that can, among other things, cause dysgeusia, for example, tree pollen. So can food allergens, which would seem to make more sense. The off-taste is usually caused by your immune system releasing antibodies and other chemicals into the bloodstream, which can often have wide-ranging effects. Some foods are more prone to cause an off-taste to develop, and these include shellfish, tree nuts, tomatoes, and additives such as MSG. This off-taste does not normally occur in conjunction with instances of food intolerance however.
Many Other Causes
Idiopathic dysgeusia has to be mentioned here mainly because it is one of the more common causes of an off-taste in the mouth, second only to medications. Idiopathic dysgeusia in layman’s terms means ‘altered taste from an unknown cause’.