Over the past three decades, undernutrition in Thailand has drastically reduced by over seven times. However, since 1995 the number of patients afflicted with non-communicable diseases, such as diabetes mellitus, has rapidly increased, even among the young. Unhealthy life styles due to urbanization are a major reason for this increase. Less physical activity and low consumption of fruits and vegetables, as well as high consumption of added free sugar, are common. Every year, the Thai people increase their consumption of energy from fat and protein, while lowering their intake of energy from complex carbohydrates. Per capita and on average, a Thai individual consumes up to 20% of total energy from added free sugar. Barker's hypothesis and Developmental Origins of Health and Disease hypothesis (DOHaD) can partially explain the increase in diabetes mellitus at this rapid rate. To alleviate the problem, the main strategy has been consumer education to reduce diabetes mellitus prevalence. Sugar elimination from infant formula is mandatory and sugar taxation is being considered. Simplified nutrition labeling is voluntarily as part of consumer education, as well as encouraging food industries to produce healthier food products. Currently, a multi-sectoral approach is used for alleviating diabetes mellitus in Thailand.