Bad body odor can be caused by liver problems. Liver disease can change the consistency of sweat, resulting in a foul smell. See your doctor if you begin to sweat at night, sweat more than you usually do, get cold sweats, or smell different (fruity). Discolored red and brownish sweat is also a sign that something is not right in your body. Check for other symptoms like bloating, a coated tongue, and rosacea (small pimples around your nose) to confirm that something is seriously wrong.
The liver processes all of the toxins in your body. When it no longer functions, those toxins unpleasantly come to the surface.