Weight Loss Aid in an Exposed Population

This study will explore whether the use of orlistat results in weight loss that is accompanied by a reduction in the body burdens of polybrominated biphenyls (PBB) and other Persistent Organic Pollutants (POPs).

Inclusion Criteria: * current or recent (within the last five years) serum PBB level of ≥1ppb, or are a member of a sub-group likely to have high serum PBB (former chemical worker, family member of former chemical worker, lived on a farm with animals that were quarantined because of PBB exposure) * at least 18 years old * currently reside in Michigan * able to participate in examinations and laboratory tests (a lipid panel, liver function test, thyroid function and and creatinine levels) done at at a local health department or other medical health facility and to be able to engage in moderate physical activity (e.g. walking) * participants with undiagnosed abdominal pain or diarrhea, Crohn's disease, Ulcerative Colitis, Celiac Disease, treated diabetes or treated thyroid disorder, will only be eligible following consultation with their primary care provider * any participant using levothyroxine will be instructed to take their dosage 4 hours before or after Orlistat in order to maintain eligibility Exclusion Criteria: * BMI\