Being on the heavier side may not be as dangerous as it was in the 1970s, according to a study Tuesday that points to the protective effects of a few extra pounds. The optimum ratio of weight and height — known as body mass index or BMI — is now on the upper side of the healthy range, according to the report in the Journal of the American Medical Association (JAMA). “Compared to the 1970s, today’s overweight individuals have lower mortality than so-called normal weight individuals,” said Borge Nordestgaard, clinical professor at the University of Copenhagen and Copenhagen University Hospital.