About one third of Americans are obese, defined as having a body mass index (BMI) of 30 or higher. (BMI is based on weight and height; someone who is 5'9" would have to weigh at least 203 to qualify as obese.) No federal law protects employees from discrimination based on obesity or weight per se; only one state (Michigan) and a handful of local governments provide this protection. However, the Americans with Disabilities Act (ADA) may protect the obese from discrimination, in some cases.
Weight discrimination (sometimes referred to as size discrimination) occurs when someone is treated differently because of his or her weight. The primary federal antidiscrimination law known as Title VII doesn't include obesity as a protected characteristic, which means it does not prohibit employers from discriminating based on weight.
The state of Michigan has outlawed employment discrimination based on weight, as have some cities and local areas, including San Francisco and the District of Columbia. If you work in a place that has such a law, your employer may not make job decisions based on your weight.
The ADA protects employees and applicants with disabilities from discrimination, and requires employers to make reasonable accommodations for employees with disabilities. The ADA states that height and weight, within normal parameters, are not disabilities. However, some courts and the Equal Employment Opportunity Commission (EEOC) have found that obesity might qualify as a disability, at least in some circumstances:
An employer who discriminates based on obesity might run afoul of laws that prohibit other types of discrimination under a disparate impact theory. A disparate impact lawsuit doesn't claim that the employer intentionally discriminated based on, for example, race or gender. Instead, it argues that the employer's facially neutral policy, practice, or selection criteria had a disproportionate negative effect on a protected group.
Obesity rates vary widely by race and gender. For example, statistics from the Centers for Disease Control show that African Americans have a much higher rate of obesity than non-Latino white Americans. An employer's policy of refusing to hire obese applicants could have the effect of screening out disproportionate numbers of African Americans, and be challenged as racially discriminatory, under a disparate impact theory.
If you believe you have been denied a job or otherwise discriminated against because of your weight, you should consider consulting with an experienced employment lawyer. A lawyer can help you assess the situation and figure out whether any legal protections apply.