Constantly detecting a smell resembling nail polish remover can be a confusing experience. This distinctive scent is the chemical acetone, and its presence originates from two entirely different sources. The odor may be a byproduct of internal metabolic processes, where the body is producing and expelling the chemical itself. Alternatively, the smell might be a phantom perception, a signal distortion that makes you perceive an odor not actually present in your environment. Identifying the source is the first step toward understanding the cause.
Metabolic Causes: When the Body Produces Acetone
The smell of nail polish remover on the breath indicates the body is metabolizing fat and generating high levels of acetone. Acetone is one of three compounds, known collectively as ketone bodies, which the liver produces when glucose is unavailable for energy. The process begins with the breakdown of fatty acids, creating ketones like acetoacetate and beta-hydroxybutyrate. Acetone is the volatile third ketone, a byproduct of acetoacetate decomposition, which is expelled through the lungs as a gas.
One common reason for this scent is nutritional ketosis, which occurs during low-carbohydrate diets or periods of fasting. When carbohydrate intake is severely restricted, the body switches its primary fuel source from glucose to fat, temporarily increasing ketone production. Excess acetone, which the body is not yet efficient at using, is released via the breath, creating the recognizable fruity or solvent-like odor. This is often a short-term side effect as the body adapts to burning fat.
A more serious cause of acetone breath is Diabetic Ketoacidosis (DKA), a dangerous complication most common in people with type 1 diabetes, but possible in type 2. DKA occurs when a severe lack of insulin prevents cells from absorbing glucose for energy. The body rapidly burns fat for fuel, leading to an uncontrolled build-up of ketones.
This concentration of acidic ketones turns the blood highly acidic, a life-threatening condition if not treated immediately. The body attempts to compensate by breathing more deeply and rapidly—a pattern called Kussmaul respiration—to expel the volatile acetone. The high concentration of exhaled acetone results in a pronounced nail polish remover scent on the breath.
Phantosmia: Smelling What Isn’t There
When the smell of acetone cannot be linked to the breath or the environment, the cause may be phantosmia, or phantom smells. Phantosmia is an olfactory hallucination where the brain perceives an odor that does not physically exist. While many cases involve unpleasant smells like burning or rotting, the perception of a chemical odor like acetone is common.
This distortion can originate from issues within the nasal cavity, where the olfactory nerves are located. Conditions like chronic sinus infections, severe upper respiratory infections, or nasal polyps can irritate or damage the nerve endings. This damage can cause the olfactory neurons to misfire, sending an incorrect signal to the brain that is interpreted as a smell.
The phantom smell can also be a symptom of a neurological event, indicating a problem in the brain itself. The perception of strange odors can sometimes be a precursor to a migraine headache, known as an aura. Phantosmia may also be associated with conditions affecting the temporal lobe, such as certain types of seizures, a previous head injury, or a brain tumor. In these cases, the smell results from abnormal electrical activity in the brain’s smell-processing centers.
Environmental and External Explanations
Before assuming the source is internal, rule out external environmental exposures that contain acetone or similar chemicals. Acetone is a highly effective solvent used in many household and industrial products. The scent can linger in the air from recent activities such as painting, using strong adhesives, or applying cleaning products.
Volatile organic compounds (VOCs) released from new items, known as off-gassing, can also mimic the scent. New furniture, carpeting, or electronic devices can emit chemical odors that resemble acetone. Exposure to sources like tobacco smoke or vehicle exhaust also contains low levels of acetone that some people may detect.
Warning Signs and Medical Consultation
If the scent of nail polish remover is coming from your breath, especially if you are not following a low-carbohydrate diet, immediate medical attention may be necessary. The most serious concern is Diabetic Ketoacidosis (DKA), which requires emergency treatment. Warning signs that accompany acetone breath include excessive thirst, frequent urination, and profound weakness.
Other DKA symptoms include rapid, deep breathing (Kussmaul breathing), stomach pain, nausea, or vomiting. Confusion, a change in mental status, or loss of consciousness are also severe indicators. Anyone experiencing the acetone odor along with these symptoms should seek emergency care immediately to check blood sugar and ketone levels.
If the smell is phantom (meaning others cannot detect it) and persists for more than a few weeks, a routine appointment with a healthcare provider is warranted. A doctor can rule out underlying issues like chronic sinus disease or neurological causes, such as previous head trauma. They may recommend testing to determine if a low-grade metabolic issue or a simple sensory irritation is the source.