At the start of a new school year, it’s a good time to evaluate your child’s health and start healthier diet and exercise habits, if needed.

Do you know if your child is overweight – or even obese? One in three U.S. children is overweight or obese, which can lead to serious health problems now and later.

National surveys show that 20 percent of preschoolers and 30 percent of school-age children are overweight, with 15 percent of school-age children considered obese. In the last 20 years, the number of overweight children has doubled, while the number of obese adolescents has tripled.

This epidemic equally affects both sexes and all races; however, African-American and Hispanic children are more at risk.

The extra pounds can cause severe cardiovascular problems, such as high blood pressure, high cholesterol and Type 2 diabetes. These risk factors in childhood can lead to serious adult problems, such as heart disease, heart failure and stroke.

Preventing or treating childhood obesity may reduce the risk of developing heart disease. To combat excess weight in your child, work to improve the diet and exercise levels of your entire family by:

* Buying more fruits and vegetables. Let your child help choose fresh produce at the store with you.

* Buying less sodas and high-calorie, high-fat snacks. Chips and cookies are acceptable as occasional treats, but healthy foods, such as fruit and whole grains, are better for routine snacks.

* Offering more water and low-fat milk. Low-fat milk offers important nutrients, such as calcium and Vitamin D, for a child’s development. Fruit juice is healthy if it’s 100 percent juice, but it must be limited because it is high in calories.

* Limiting TV and video games. Turn off the TV, and encourage children to be physically active at least 20 minutes a day.

Children grow at different rates at different times, which may make it difficult for you to determine if your child is overweight. Take your child for regular medical checkups, so your healthcare provider can see if your child’s height and weight are considered healthy.