pascuala: this woman has anxiety and dreams a lot. it has made her sick.leansing. reporter: junk food is readily available here and has come to replace the traditional diet of maize, beans, and chili. and then there's the water problem. coca cola is permitted to tap more than a million liters of water every day, all approved by the state, says marcos arana. fizzy drink is often easier to get than clean drinking water. marcos: nobody is monitoring how much water is actually being taken. there's no oversight. the growing scale of production at this plant puts the supply for the rest of the population at risk. reporter: the company refutes this, saying it is not taking water away from anyone. instead, it donates water tanks and recycling containers, and has reduced the amount of sugar in many of its products. the neighboring state of oaxaca is not relying on that. teacher diana lopez has declared war on soft drinks. one in three children is overweight. she counts the spoons of sugar in a single glass of soda. diana: we drink this amount of sugar in a single g