A new study has said that cigarette smoking, hypertension, excess weight and sedentary lifestyle are the main causes of death in the US.

At the same time, the study also said that all these causes are preventable.

Researchers from Harvard School of Public Health (HSPH), Universities of Toronto and Washington conducted the study.

The researchers found that smoking claims 467,000 people each year, high blood pressure (BP) kills 395,000 lives and obesity accounts for 216,000 deaths.

They also said that smoking effects are responsible for about 1 in 5 deaths in Americans who are over 30 years of age, whereas and high BP account for one in six deaths.

It is the most extensive research up till now to consider how diet, daily life and metabolic risk elements for chronic disease contribute to death in the US.

Goodarz Danaei, doctoral student at HSPH and study co-author said, “The large magnitude of the numbers for many of these risks made us pause.”

Majid Ezzati, Associate Professor at HSPH and study co-author, “To have hundreds of thousands of premature deaths caused by these modifiable risk factors is shocking and should motivate a serious look at whether our public health system... is currently focusing on the right set of interventions.”

The study researchers gauged the number of preventable deaths by looking at 12 different changeable risk factors that consists of overweight and obesity, high salt diets, high blood glucose, high LDL cholesterol, physical inactivity, and low fruit and vegetable intake.