The health risks of obesity are well-documented, but there's a financial downside, too -- data shows obese people also earn less money, especially women.

How much less? George Washington University researchers found that in 2004, overall average annual incomes were about $9,000 less for obese women and almost $5,000 less for obese men compared with normal weight workers.

But the income disparities weren't nearly as marked among African-American men and women. In fact, obese black men earned more than normal-weight black men in 2004 and 2008, and obese and normal-weight black women earned similar wages.

Still, including lower salaries and indirect costs, such as lost productivity, and direct expenses, such as medical care, last year the average annual costs of obesity were $4,900 for a woman and $2,600 for a man.

“This research broadens the growing body of evidence that shows that in addition to taxing health, obesity significantly affects personal finances,” said Christine Ferguson, a professor in George Washington University's department of health policy. “It also reinforces how prevalent stigma is when it comes to weight-related health issues.”

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