Brief Answer:
Various possible causes

Detailed Answer:
Dear Sir, I have gone through your question and I understand your concerns ...

This could be due to bacterial infection of the sebaceous gland by an acid producing bacteria .. This may mostly occur if you are overweight, immune-compromised or does not get enough showers with soap and water...

Also, please note, this could be a sign of diabetes, as insulin deficiency leads to abnormal break down of sugar leading to overproduction of ketone bodies that alter the smell out your sweat...

In this scenario, I would recommend that you take a blood test of glucose level both fasting and post-prandial together with HB A1c blood test to detect any diabetic or prediabetic status ...

Also, I would recommend that you lose extra weight in case you are overweight and please try to get a shower daily (if at all this is the scenario)...

I hope I answered your question
Let me know if I can assist you further

Regards

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