While the original ADA statute makes no mention of obesity under ADA, the 2008 amendments to ADA make it somewhat posible that obesity may be seen as a protected disability under ADA at some point in the future. The 7th Circuit joined the 2nd, 6th and 8th circuits in ruling that, absent evidence that it was caused by an underlying physiological disorder or condition, extreme obesity is not a physical impairment under the ADA. The 1st Circuit found otherwise.
Whether obesity qualifies as a disability under the ADA is largely dependent on a variety of factors, including jurisdiction. Most jurisdictions that have considered the issue have held that obesity alone, without an underlying physiological disorder, does not constitute a protected physical impairment. Even still, cities should proceed cautiously when making employment decisions that could involve these issues, and should consult with the their city attorney, or risk underwriter to ensure they are acting in accordance with the law.