Metabolic Imbalances: Diet, Diabetes, and More
Metabolic changes within the body are one of the most common reasons for a person to exude a chemical odor. The way the body processes and utilizes energy can produce volatile compounds that are then released through breath, sweat, and urine.
Ketosis and the Keto Diet
When following a ketogenic (keto) diet, the body enters a metabolic state called ketosis, where it burns fat for energy instead of carbohydrates. This process produces ketones, including acetone, a chemical also found in nail polish remover. The presence of excess acetone is released through the breath and sweat, which can give off a distinct fruity or chemical smell.
Diabetic Ketoacidosis (DKA)
In people with uncontrolled diabetes, a life-threatening condition called diabetic ketoacidosis (DKA) can occur. When insulin levels are too low, the body begins breaking down fat for energy, leading to a dangerous buildup of ketones. One of the tell-tale symptoms of DKA is a fruity or acetone-like smell on the breath, which is a medical emergency requiring immediate attention.
Trimethylaminuria (TMAU)
Also known as "fish odor syndrome," TMAU is a rare metabolic disorder where the body cannot break down trimethylamine (TMA), a compound with a foul, fishy smell. TMA builds up in the body and is released in sweat, urine, and breath. This condition is often inherited but can also be triggered by excess dietary choline or in people with kidney or liver disease.
Organ Failure and the Buildup of Waste Products
When organs such as the kidneys or liver fail, they lose their ability to filter and process waste products from the body. The resulting toxic buildup can lead to a noticeable chemical odor.
Kidney Failure (Uremic Fetor)
During kidney failure, the kidneys cannot effectively filter waste products, such as urea, from the blood. When urea builds up and interacts with saliva, it is converted into ammonia. This process can cause the breath to have a strong, ammonia-like or urine-like smell, a condition known as uremic fetor. Sweat can also carry this ammonia odor, especially after exercise or when dehydrated.
Liver Disease (Fetor Hepaticus)
Advanced liver disease, such as cirrhosis, can prevent the liver from properly filtering sulfur-containing compounds. The buildup of these substances in the body results in a distinct, pungent, and slightly sweet or musty odor on the breath, known as fetor hepaticus. The smell is sometimes compared to rotten eggs or garlic.
Sensory and Neurological Causes: When the Smell Is in Your Head
In some cases, the chemical smell is not actually emanating from the body but is a phantom or distorted sensation perceived by the individual.
Phantosmia
Phantosmia is a condition where a person smells things that are not present, known as an olfactory hallucination. The phantom smells can vary but are often unpleasant and metallic, burnt, or chemical in nature. Causes can range from sinus infections and head injuries to more serious neurological conditions like epilepsy, stroke, or brain tumors.
Parosmia
Parosmia is a related condition where a person's normal sense of smell is distorted, and everyday odors are perceived differently. For example, the scent of a flower might be perceived as a chemical smell. This often occurs after damage to the olfactory system from a severe respiratory infection, such as COVID-19.
Other Contributing Factors
Several other less common or environmental factors can contribute to unusual body odors.
Medications
Some medications can alter the body's chemistry and metabolic processes, leading to changes in sweat or breath odor. These include certain antibiotics and antidepressants. Consult a doctor if you suspect a medication is causing an unusual smell.
Dietary Factors
Aside from metabolic disorders, a diet heavy in certain foods can temporarily affect body odor. Pungent foods like garlic, onions, and certain spices are broken down and release odorous compounds through the pores.
Comparison of Chemical Body Odors
| Condition | Chemical Scent | Related Symptoms |
|---|---|---|
| Ketosis (Diet) | Fruity, nail polish remover | Fatigue, headache (keto flu) |
| DKA (Diabetes) | Sweet, fruity | High blood sugar, thirst, confusion |
| Kidney Failure | Ammonia, urine-like | Fatigue, swelling, changes in urination |
| Liver Failure | Sweet, musty, garlicky | Jaundice, abdominal pain, fluid retention |
| TMAU (Metabolic) | Fishy, rotten | No other systemic symptoms |
| Phantosmia (Sensory) | Phantom metallic/burnt smell | Smell disorder, often following an illness or trauma |
When to Seek Medical Attention
While some diet-related odors may be temporary, a persistent or sudden chemical smell from your body should be evaluated by a healthcare professional. It is especially important to seek immediate medical care if the odor is accompanied by other symptoms such as confusion, severe fatigue, jaundice, or changes in urination.
For more detailed information on body odor and associated health changes, refer to the Cleveland Clinic's article on the topic.
Conclusion
A chemical smell from a person can have numerous origins, ranging from harmless dietary adjustments to serious underlying medical conditions involving the metabolism or organ function. Keeping track of other symptoms and understanding the specific type of odor can help identify the cause. Whether it's a metabolic shift from a low-carb diet, a sign of diabetic ketoacidosis, or an indication of kidney or liver issues, paying attention to this change in your body can be a critical step toward maintaining your overall health.
