Maria del Carmen Abadía lives in one of Mexico's rainiest regions, but she has running water only once every two days. When it does trickle from her tap, the water is so heavily chlorinated, she said, it's undrinkable. So, many residents drink Coca-Cola, which is produced by a local bottling plant, can be easier to find than bottled water and is almost as cheap.
The effect on public health has been devastating. The mortality rate from diabetes in Chiapas increased 30 percent between 2013 and 2016, and the disease is now the second-leading cause of death in the state after heart disease, claiming more than 3,000 lives every year.