why does my sweat smell like ammonia

Sweat that smells like ammonia usually means your body is breaking down protein for energy and releasing extra nitrogen waste (ammonia) through your sweat instead of fully processing it in the liver and kidneys. Itâs often harmless, but it can also flag diet, hydration, or (rarely) medical issues.
Quick Scoop
Why it happens:
- Your body burns amino acids (from protein) when carbs are low or during intense exercise, creating ammonia as a byâproduct.
- If ammonia builds up faster than your liver and kidneys can convert it to urea and clear it, some spills into sweat, giving that sharp, cleaningâproductâlike smell.
Main causes
1. Diet and fuel use
- Highâprotein, lowâcarb diets (keto, bodyâbuilding plans, lots of shakes/meat) push your body to use amino acids for energy, raising ammonia production.
- Low glycogen stores from longâduration or very intense workouts can also force protein breakdown, especially if you havenât eaten enough carbs beforehand.
2. Exercise intensity
- Hard or prolonged training increases protein catabolism, which can temporarily spike ammonia in sweat and blood.
- Many people notice the smell right after a tough session, then it fades once recovery starts.
3. Dehydration
- When youâre low on fluids , sweat becomes more concentrated, so any ammonia present smells stronger.
- Chronic dehydration can also slow kidney clearance of nitrogen wastes, indirectly contributing to the odor.
4. Underlying health issues (less common)
- Kidney disease can impair urea/ammonia clearance, sometimes causing ammoniaâlike odors in sweat or breath.
- Liver dysfunction can reduce the liverâs ability to convert ammonia to urea, leading to buildup.
- Metabolic conditions or severe malnutrition can also alter how your body handles nitrogen.
What you can do
Lifestyle and diet tweaks
- Balance macros: Add more complex carbs (oats, rice, potatoes, fruit) around workouts so your body burns glucose instead of protein.
- Moderate protein: Unless medically advised, avoid extreme highâprotein intakes; aim for about 1.2â2.2 g protein per kg body weight depending on activity level.
- Hydrate well: Aim for enough water that your urine is pale yellow; more if you sweat heavily or live in a hot climate.
- Time your meals: Eat a carbârich snack or meal 1â3 hours before intense exercise to top up glycogen.
Exercise and hygiene
- Adjust intensity/duration: If the smell appears only after very hard sessions, consider shorter, slightly less intense workouts and build up gradually.
- Shower promptly: Washing sweat off quickly reduces bacterial breakdown on the skin, which can worsen body odor overall.
- Use antiperspirant/deodorant: A good antiperspirant can cut sweat volume; a strong deodorant can mask or neutralize odors.
When to see a doctor
See a clinician if:
- The ammonia smell is constant , even at rest and with normal diet.
- You have fatigue, nausea, swelling, shortness of breath, confusion, or changes in urine (foamy, dark, or very infrequent).
- Youâre on a very restrictive diet , have lost weight rapidly, or have a known kidney or liver condition.
In those cases, a doctor can check kidney function, liver enzymes, and electrolytes and rule out more serious metabolic issues.
Quickâreference table
Cause| Whatâs happening| What to try
---|---|---
Highâprotein, lowâcarb diet| Body burns amino acids â more ammonia| Add more
carbs around workouts; moderate protein intake 135
Intense/long exercise| Extra protein breakdown during effort| Lower intensity
slightly; fuel with carbs before training 1410
Dehydration| Sweat more concentrated â stronger odor| Drink more water; check
urine color 357
Kidney or liver issues| Poor ammonia clearance| See a doctor for blood/urine
tests 29
If you tell a bit more (diet type, workout routine, any other symptoms), a more tailored âthisâspecificâsituationâ explanation is possible. Information gathered from public forums or data available on the internet and portrayed here.