Bet you didn't see this one coming.
In a paper published online Monday in the Public Library of Science Medicine journal, Dutch researchers found that the health costs of thin and healthy people in adulthood are more expensive than those of either fat people or smokers.
Van Baal and colleagues created a model to simulate lifetime health costs for three groups of 1,000 people: the "healthy-living" group (thin and non-smoking), obese people, and smokers. The model relied on "cost of illness" data and disease prevalence in the Netherlands in 2003.
The researchers found that from age 20 to 56, obese people racked up the most expensive health costs. But because both the smokers and the obese people died sooner than the healthy group, it cost less to treat them in the long run.