Summer may be bad for your child's health.

Research compiled by the National Summer Learning Association and released Monday found that kids are at risk for gaining weight and not eating healthfully during the summer vacation.

When kids are unhealthy it affects their ability to learn, said the non-profit that promotes learning during the summers months.

The group encourages parents to take a proactive role to make sure their kids are getting enough exercise and not snacking too much while on vacation.

Kids may gain weight because they may snack more during the day instead of having structured eating times at school. Children are also getting less physical activity because some don't have safe places to play and others can't afford summer camps. Some prefer playing video games to riding a bike.

Poorer children are likely not to eat as healthy because they don't have adequate amounts of food at home. During the school year, they may be fed through the free lunch program.

The National Summer Learning Association is working with United Way Worldwide on a campaign to get kids mroe active and healthy in the summer.