In a finding that contradicts some recent research suggesting that being overweight protects us against some causes of death, a Boston University study has found a 6 percent increased risk of dying from any cause among people with a history of being overweight. What’s overweight? The researchers defined it as having a body mass index, or BMI, of 25 to 29.9. Curious? Calculate your BMI here. A Boston University news release reports that the researchers examined risks for all-cause and cause-specific death associated with being overweight or obese among more than 225,000 participants in three large prospective studies. It gauged the maximum BMI (body mass index) of participants across 16 years of weight history, and examined deaths that occurred within an average of 12 years of follow-up. The highest risk for death occurred among people who had significant drops in weight, which, unsurprisingly, the authors attributed to unintentional weight loss caused by illness. Because most participants were white and highly educated, the researchers suggest that the results may not apply to more diverse populations.