discovers links between elusive symptoms and clinical tests

Human breath and body odors have been used for diagnosis of serious and life-threatening conditions since the dawn of medical practice. More recently, it has been recognized that malodors without accompanying physical symptoms could be a sign of psychologically but not physically debilitating disorders such as Trimethylaminuria (TMAU). Self-reported intermittent odors without apparent cause, are, however, still treated with suspicion by medical professionals. Most cases of socially-disabling idiopathic malodor remain undiagnosed and there are no guidelines for diagnostic tests nor treatment options that extend beyond TMAU. Internationally-recruited volunteers with undiagnosed body odor and halitosis enrolled to participate in our study, registered as NCT02692495 at clinicaltrials.gov. Each volunteer underwent several blood and urine tests conducted by Biolab Medical Unit, a medical referral laboratory in London, specializing in nutritional and environmental medicine. Intestinal permeability measurements were strikingly different for subjects that named the nose/mouth as the malodor source(s) versus other, often unidentified, body regions. Furthermore, metabolite levels in blood and urine allowed matching of participants by dietary sensitivities and the type of odor reported, emphasizing the potential of harnessing patients' olfactory observations. In discussing the anecdotal "People are Allergic to Me" condition (PATM), we show how it fits into the picture.