What Foods Cause Ammonia Smell? An In-Depth Guide

December 26, 2025 •

4 min read

Did you know that consuming a diet high in protein and low in carbohydrates is a common cause of the body producing an ammonia smell? This happens because your body begins to break down protein for energy, a process that releases ammonia as a byproduct. Factors like hydration and specific foods further influence this metabolic response, making the odor more noticeable.

Quick Summary

A diet high in protein or low in carbohydrates can trigger an ammonia-like odor in sweat and urine. This is a metabolic reaction and is often exacerbated by dehydration, which concentrates waste products in the body.

Key Points

High-Protein Diet: Excess protein intake, especially without sufficient carbohydrates, forces the body to metabolize protein, producing ammonia as a byproduct that is excreted in sweat and urine.
Low-Carb (Keto) Diet: When the body enters ketosis due to carb restriction, it burns fat and protein for fuel, increasing the production of ammonia and ketones, which can cause a distinct odor.
Dehydration Magnifies Odor: Insufficient water intake concentrates waste products like ammonia in bodily fluids, making the resulting odor much more potent and noticeable.
Asparagus Contains Sulfur Compounds: Asparagusic acid in asparagus metabolizes into sulfur-containing chemicals that are excreted through urine, leading to a temporary, pungent smell in some individuals.
Intense Exercise: Strenuous workouts can deplete glycogen stores, causing the body to burn muscle protein for energy and resulting in an ammonia smell in sweat.
Underlying Health Conditions: Persistent ammonia odor that is not resolved by diet or hydration changes can indicate more serious issues like kidney or liver disease and warrants medical attention.

The Connection Between Diet and Body Odor

While many people associate body odor with poor hygiene, a significant number of cases are related to dietary and metabolic factors. A distinctive ammonia smell in sweat or urine is a tell-tale sign that the body's nitrogen metabolism is out of balance. This often occurs when the body's primary fuel source shifts from carbohydrates to protein and fat, leading to an increased production of ammonia. The liver is tasked with converting this toxic ammonia into urea, which is then excreted through the kidneys and sweat glands. When the body produces more ammonia than the liver can process efficiently, the excess is released through perspiration and urine, causing the potent odor.

High-Protein and Low-Carbohydrate Diets

One of the most common dietary culprits is a high-protein, low-carbohydrate eating plan, such as the ketogenic (keto) diet. When carbohydrate intake is severely restricted, the body's glycogen stores become depleted. To find an alternative fuel source, the body turns to breaking down protein from muscle tissue and dietary intake, a process known as gluconeogenesis. This results in a higher concentration of amino acids being metabolized. The deamination of these amino acids, which is the removal of their nitrogen-containing amino group, produces a significant amount of ammonia. The body then excretes this excess ammonia, resulting in the characteristic smell.

Specific High-Protein Foods

Certain protein-rich foods can contribute more directly to this issue. While all protein will increase ammonia production, some foods are consumed in higher quantities, leading to a more noticeable effect. These include:

Red meat
Poultry, especially chicken
Eggs
Fish and other seafood
Protein supplements and shakes

The Role of Dehydration

Dehydration is a critical exacerbating factor that intensifies any diet-related ammonia smell. When a person is not drinking enough water, their sweat and urine become more concentrated. This means that the same amount of ammonia is being excreted in a smaller volume of fluid, making the odor much more pungent and noticeable. This is particularly relevant for individuals on high-protein or low-carb diets, as the metabolic processes already increase ammonia production. Staying adequately hydrated is one of the simplest and most effective ways to dilute these waste products and minimize the odor.

Specific Vegetables and Spices

Beyond protein metabolism, some specific foods contain compounds that can alter the smell of urine or sweat. Asparagus is a well-known example, containing asparagusic acid, which is broken down into sulfurous compounds that are excreted in urine, sometimes causing a distinctly pungent odor. Other foods containing sulfur, such as garlic and onions, can also contribute to a stronger body odor. These effects are often benign and temporary.

Comparison of Diet Effects on Body Odor


Dietary Factor	Primary Energy Source	Ammonia Production	Typical Body Odor Effect	Risk of Ammonia Smell
Balanced Diet	Carbohydrates	Normal	Minimal odor	Low
High-Protein Diet	Primarily protein	Increased	Noticeable odor in sweat and urine	High
Low-Carb / Keto	Fat and protein	Significantly Increased	Distinct, often pungent ammonia smell	Very High
Dehydration	All sources	Concentrated	Intensifies any existing metabolic odor	Intensifies other factors

Lifestyle and Metabolic Considerations

While food is a major factor, lifestyle choices and individual metabolic differences also play a role. Intense exercise, for instance, can deplete carbohydrate stores and force the body to burn protein for fuel, leading to a temporary ammonia smell in sweat even for individuals on a balanced diet. Genetic factors can also influence how efficiently the body processes certain compounds, such as asparagusic acid, meaning not everyone will experience the same odor effects. For most people, adjusting diet and hydration levels can resolve the issue, but persistent odor can sometimes indicate underlying health conditions such as kidney or liver disease, requiring medical consultation.

Conclusion

In summary, what foods cause an ammonia smell are primarily those that are high in protein, especially when consumed in the absence of sufficient carbohydrates. This metabolic shift forces the body to produce more ammonia, a byproduct of protein breakdown, which is then excreted through sweat and urine. Other contributing factors include dehydration, which concentrates waste products, and certain sulfur-containing vegetables like asparagus. For most people, adjusting protein and carbohydrate intake and staying well-hydrated can effectively manage the odor. However, if the smell persists despite these changes, it may be a sign of an underlying medical issue, and it is recommended to consult a healthcare professional. For more in-depth information on the biochemical processes involved, you can refer to authoritative sources such as Biochemistry, Ammonia from StatPearls.

How to Reduce the Ammonia Smell

Modify your diet: Rebalance your macronutrients by increasing healthy carbohydrate intake and moderating protein, especially if on a low-carb diet.
Stay hydrated: Drink plenty of water throughout the day to dilute the concentration of ammonia in your bodily fluids.
Ensure adequate carb intake before exercise: If you are an athlete, consuming carbohydrates before and during strenuous workouts can prevent your body from using protein for energy.
Address specific foods: If you notice a link between certain foods like asparagus, garlic, or onions and an odor, consider limiting your intake.
Consult a professional: If the smell is persistent or accompanied by other symptoms, speak with a doctor to rule out underlying medical issues.

Frequently Asked Questions

If your sweat smells like ammonia during or after a workout, it often indicates that your body is using protein for fuel. This happens when you don't have enough carbohydrates to burn for energy, causing your body to break down muscle tissue to get amino acids.

Yes, a high-protein diet, particularly when low in carbohydrates, can lead to an ammonia smell. The body produces ammonia when it breaks down excess protein, and this metabolic waste is then excreted through sweat and urine.

Absolutely. Dehydration is a significant factor that concentrates your sweat and urine. When there is less water to dilute metabolic waste products, the concentration of ammonia increases, making the odor stronger and more pungent.

The keto diet, a very low-carbohydrate plan, forces the body into a state of ketosis where it burns fat for energy. This often involves increased protein metabolism, which elevates ammonia levels and can cause an ammonia-like smell in both breath and sweat.

For most healthy individuals, the ammonia smell caused by dietary changes like high protein or low carbs is temporary and harmless. However, if the smell is persistent and not linked to diet or exercise, it could signal an underlying health issue and should be checked by a doctor.

While not a product of protein metabolism, asparagus contains asparagusic acid, which breaks down into sulfur-containing compounds after digestion. These compounds can give urine a strong odor that some people describe as similar to ammonia, though it is a different process.

The most effective way to eliminate the ammonia smell is to balance your diet by ensuring adequate carbohydrate intake, stay well-hydrated by drinking plenty of water, and ensure good personal hygiene. For athletes, consuming carbohydrates before intense exercise can help prevent the issue.