The study shows evidence of obesity being linked to life expectancy. (Representational Photo)

Being overweight shaves about a year off one's life expectancy, a price which soars to about 10 years for the severely obese, a large-scale study reported.It refuted earlier findings that carrying a few extra kilos (pounds) poses no perils.Instead, the study pointed to evidence that the risk of dying before your 70th birthday grows "steadily and steeply" along with an expanding waistline."This study definitely shows that being overweight or obese is associated with a risk of premature death," lead author Emanuele Di Angelantonio from the University of Cambridge said.The risk of coronary heart disease, stroke, respiratory disease and cancer "are all increased," he said.Using data from almost four million adults on four continents, the study in The Lancet medical journal found that overweight people lost about a year of life expectancy on average, and "moderately obese" people about three years."Severely obese people lose about 10 years of life expectancy," Di Angelantonio said- which represents a one-in-two chance of dying before 70.A large international team of researchers sifted through data garnered from more than 10.6 million people in 239 large studies conducted between 1970 and 2015 in 32 countries in North America, Europe, Australia, New Zealand, and east and south Asia.The collating effort was described as the largest-ever pooled dataset on being overweight and mortality.To rule out the impact of other mortality risks, the team excluded current or former smokers, those who had chronic disease at the beginning of the study, and those who died within the first five years- and were left with a sample group of 3.9 million adults.