Mexico has one of the highest rates of type 2 diabetes in the world, with 12% of the population suffering from the condition, compared with 9% of people in the United States. The Mexican government is so worried that it recently declared a state of emergency and introduced a tax on soda and junk food. But a new study shows that some Mexicans may be at higher risk for developing diabetes, no matter how healthy their diets are. The reason may be their Maya ancestry, which carries with it genetic variations associated with the disease.