Being overweight is associated with a increased chance of dying early — no matter what the exact cause of death. After a study with some 4 million participants from four of the six inhabited continents, researchers from the Global BMI Mortality Collaboration at the University of Cambridge published their findings in the Lancet medical journal Wednesday.
The study began with over 10 million participants but the number was whittled down to just under 4 million by excluding smokers and those with chronic diseases. To draw as clear a link as possible between all-cause mortality (a term used to define the total number of deaths in a given place, irrespective of the causes) and obesity, the study excluded from the final data analysis any participants who died within 5 years of joining the study.
“If the overweight and obese population had WHO-defined normal levels of BMI, the proportion of premature deaths that could be avoided would be about one in five in North America, one in six in Australia and New Zealand, one in seven in Europe, and one in 20 in east Asia,” said the report.
BMI, short for body mass index, is a common classification for height-to-weight ratios, and is calculated by dividing a person’s weight in kilograms by the square of the height in meters. For example, if you weigh 70 kilograms (154.3 pounds) and stand 1.75 meters (5 feet 9 inches) tall, you have a BMI of 22.9.
The World Health Organization (WHO) calls BMI between 25 and 29.99 pre-obese overweight; BMI of 30 and above is classified into 3 different kinds of obese.
The Lancet study showed that men were about three times more likely to suffer from obesity-related premature deaths than women. Younger people were found to be at higher risk than older people.
The various kinds of diseases with increased chances of causing fatality, when combined with obesity, include cardiovascular, respiratory and cancer.
According to WHO, 39 percent of the world’s adult population in 2014 — which is more than 1.9 billion people — was overweight. Over 600 million were obese. Globally, there were also 41 million children under the age of 5 who were obese in 2014.