One in five adults worldwide will be obese by 2025: study

One-fifth of adults worldwide will be obese by the year 2025 if present trends continue, warns a major new study which found that the world now has more overweight than underweight people. The research published in The Lancet journal found that rates of obesity surpassed those of underweight in women in 2004 and in men in 2011. In the past 40 years, there has been a startling increase in the number of obese people worldwide - rising from 105 million in 1975 to 641 million in 2014, researchers said.

The age-corrected proportion of obese men has more than tripled (3.2 per cent to 10.8 per cent), and the proportion of obese women has more than doubled (6.4 per cent to 14.9 per cent) since 1975. At the same time, the proportion of underweight people fell more modestly - by around a third in both men (13.8 per cent to 8.8 per cent) and women (14.6 per cent to 9.7 per cent). Over the past four decades, the average body mass index (BMI) increased from 21.7 kg per square metre to 24.2 kg per square metre in men and from 22.1 kg per square metre to 24.4 kg per square metre in women, equivalent to the world's population becoming on average 1.5 kg heavier each decade.

If the rate of obesity continues at this pace, by 2025 roughly a fifth of men (18 per cent) and women (21 per cent) worldwide will be obese, and more than 6 per cent of men and 9 per cent of women will be severely obese (35 kg per square metre or greater), researchers said. However, excessively low body weight remains a serious public health issue in the world's poorest regions, and the researchers warn that global trends in rising obesity should not overshadow the continuing underweight problem in these poor nations.

For example, more than a fifth of men in India, Bangladesh, Timor-Leste, Afghanistan, Eritrea and Ethiopia, and a quarter or more of women in Bangladesh and India are still underweight, researchers said. "Over the past 40 years, we have changed from a world in which underweight prevalence was more than double that of obesity, to one in which more people are obese than underweight," said Majid Ezzati from Imperial College London. "If present trends continue, not only will the world not meet the obesity target of halting the rise in the prevalence of obesity at its 2010 level by 2025, but more women will be severely obese than underweight by 2025," Ezzati said.

The findings come from a comprehensive new analysis of the global, regional and national trends in adult BMI between 1975 and 2014. Researchers pooled data from 1,698 population-based studies, surveys and reports totalling 19.2 million men and women aged 18 years or older from 186 countries (covering 99 per cent of the world's population).