The link between obesity and death from heart disease may be even worse than previously thought, but health problems associated with being underweight  may have been exaggerated, a new study shows.

Previous studies have shown that a higher than normal body mass index (BMI), a barometer of unhealthy weight levels, is associated with higher rates of death from cardiovascular disease. Studies also have shown a link between being underweight, or having a low BMI, with increased mortality from such problems as respiratory disease and lung cancer.

But scientists at the University of Bristol in the U.K. and the Karolinska Institute in Sweden now say they’ve found that the risks of death from cardiovascular disease for people who are overweight or obese may have been understated, and the adverse consequences of having a low BMI have been overstated.

via Heart Risk of Obesity Greater Than Thought.