According to new research published in the journal ‘The Lancet,’ deaths caused by cancer are more common than by heart disease in high-income countries. We are seeing a new epidemiologic transition - from heart disease to cancer as the leading cause of death - which is occurring first in high income communities, Dr. Latha Palaniappan, via CNN. Researchers suspect the shift is a result of increased efforts by high-income countries to prevent and treat heart disease and their inability to prevent cancers. The study also found that death by heart disease was three times more common in low-income and middle-income countries. Globally, cardiovascular disease still ranks as the top cause of death.