STUDIO CITY (CBSLA.com) — Many schools are sending notes home to parents, telling them their children are overweight.

Lauren Schmitt, a registered dietitian, starts the school year by checking out the weight of hundreds of preschoolers in the San Fernando Valley.

“We look at growth charts and percentiles. And when a child is at 95 percent of their…we can look at weight for age or weight for height…that child would be considered obese,” she said.

By October, CBS2’s Suraya Fadel reported that parents will get what is called “healthy or unhealthy” letters. Kids call them “fat letters.”

Schmitt said out of the 900 2 to 5-year-old children she looks at, roughly 200 are listed as obese.

“We let the parents know in a gentle fashion, but we also send out a ton of handouts to try to help that family,” she said.

Experts said 19 states around the country are cracking down on childhood obesity with similar letters.

“Every year there are a few phone calls from parents who are upset,” said Schmitt.

Many districts in Southern California, such as Riverside County, choose to follow state guidelines and instead send test results of the child’s body mass index to their parents.

“It shouldn’t be a stigma. It’s not a way to categorize someone. It’s just showing that this child has increased risk to be obese as an adult, which then could lead to quite a few chronic diseases,” said Schmitt.

The dietitian said the goal is to empower and educate parents with the tools to make healthier lifestyle choices for children.