ZocdocAnswersIs there a reason that my sweat has a strange odor?

Question

Is there a reason that my sweat has a strange odor?

My friends think I'm nuts, but I swear that when I sweat it smells funny. Almost like ammonia. Like the sweat on my forehead and arms smells like this. What could cause this or is it all just in my head?

Answer

This is a very common observation. It is most common for sweat to have a strong ammonia odor after a long workout. This occurs because, during a long workout, the body may begin to switch from burning carbohydrates to burning protein for energy. When this transition occurs, by products of protein breakdown start to be produced, and one of those by products is ammonia, which just happens to be excreted in sweat! In other words, this is a normal process and is not a sign that you have any medical problem. However, it may be a sign that you are not getting enough calories before your workouts. In particular, you may want to try experimenting with the amount of carbohydrates that you load before a long workout to see if you can reduce the breakdown of protein. However, on a very long run or other long aerobic workout, burning some protein may not be avoidable. Another factor which can increase the ammonia odor is not drinking enough water, as this causes less sweat to be produced, meaning the ammonia that is excreted is more concentrated. Please talk to your primary care doctor to get more specific information!

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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