did you express to your doctor that you have Body Odor ? does the doctor know or agree with you that you have a problem? do you or the doctor know where the odor is coming from?
You should try probiotics. Specifically "Primal Defense" . This probiotic really helps with constipation and IBS and it keeps your gastrointestines healthy and full or good bacteria and it eliminates the bad bacteria. It may also help with your fecal odor.
As for your hair...Ive never heard of Metamucil making hair fall out. You may have a thyroid problem. Its not that expensive to get some blood drawn and to check your thyroid.