I've noticed this somewhat too.. it seems to correlate with negative emotional wellbeing and nerviousness.. I will smell it somewhat when I am really nervious or down upon myself for whatever reason in public situations, but 30 minutes later when I'm getting brisk aerobic exercise and feeling better, releasing tension, I won't smell a thing.
Anyone else have a correlation between odor and emotional state?
They say you must address emotional wellbeing before physical wellbeing.