The world’s two leading causes of death are heart disease, which killed 17.8 million people in 2017, and cancers, which killed 9.6 million that year. The third biggest killers were respiratory diseases, killing 3.9 million. However, all of the above are actually groups of diseases. If we consider specific diseases, then ischemic heart disease is the biggest killer globally, followed by stroke and chronic obstructive pulmonary disease.