While India and China continue to have the largest number of underweight people in the world, both the countries have also broken into the top five in terms of obesity, a new study published in The Lancet jorunal has found.With 102 million men and 101 million women underweight, India leads the world in being home to over 40% of the global underweight population. China is a distant second with about 8% of underweight men and over 12% of underweight women.However, India has also seen a surge in obesity . It had 0.4 million obese men, or 1.3% of the global obese popula tion in 1975, but in 2014, it zoomed into the fifth position with 9.8 million obese men, or 3.7% of the global population.Among women, India has jumped to the third rank with 20 million obese women (5.3% of global population). China has followed a si milar trajectory to In dia when it comes to obesity, rising from 13th rank in 1975 for men and 10th among women to the first rank in 2014 for both men and women. It now has the most number of obese persons in the world edging out the US.“If these trends continue, by 2025, global obesity prevalence will reach 18% in men and surpass 21% in women; severe obesity will surpass 6% in men and 9% in women,“ the study , led by Majid Ezzati, professor at the School of Public Health, Imperial College London said.“Nonetheless, underweight remains prevalent in the world's poorest regions, espe cially in south Asia,“ it added.The study used data from national and smaller studies representing 19.2 million adults from 186 countries to arrive at its conclusions. It used the standard definitions of underweight (Body Mass Index less than 18.5 kg per sqm) and obesity (BMI greater than 30 kg per sqm). BMI is a ratio of weight and height, standardised to various age groups.Both underweight and obesity are well known causes for several fatal condi tions like heart diseases, diabetes and others.Globally , underweight population has declined while obese population has increased since 1975, the study found. In 1975, 13.8% men and 14.6% women were underweight. These proportions declined to 8.8% for men and 9.7% for women in 2014. Obese population shares were just 3.2% for men and 6.4% for women in 1975 which have risen to 10.8% for men and 14.9% for women in 2014.