A global study published in The Lancet says that if current trends continue, 18% of men and 21% of women will be obese by 2025. The study examined obesity rates in 200 countries and demonstrated that the number of individuals affected by obesity increased from 105 million in 1975 to 641 million in 2014. The number of underweight people increased from 330 million to 432 million during the same period.