Answer:
A mixture of other factors — like behavioral patterns and genetics. They are accounted for a big number of early deaths.
A CDC study has stated that behavioral patterns ( which take up roughly 40 percent of the deaths) and genetics ( somewhere around 30 percent of all the deaths) are the most common causes of premature deaths. Social circumstances (which take up 15 percent), health care (around 10 percent), and environmental exposure ( somewhere around 5 percent).