We all know the dire statistics: According to the Centers for Disease Control and Prevention, 20 percent of kids ages 6-11 are now considered obese, up from only 7 percent in 1980. You probably also know two key weapons against increasing girth in kids: more exercise and a lot less junk food and soda.

But knowledge is power, so a logical next step is to educate kids about how to evaluate the foods that go in their mouths. That means understanding the basics of food labels.

Feeling intimidated? You're not alone. According to a 2011 survey of 1,009 U.S. parents conducted by Kelton Research and commissioned by CLIF Kid, 42 percent say that reading nutrition labels is more difficult than reading assembly instructions for IKEA furniture.

But you and your kids don't have to be scientists to make better food choices; just start with your ABCs."Once children know how to read, they are ready to start learning how to read food labels," says Jolly Backer, CEO of Fresh Healthy Vending, a forward-thinking company started in 2010 that's placing healthy-food vending machines in schools, offices, and other locations nationwide. "The more kids know about what they're eating, the more empowered they will be about making healthier food choices."

Here's how to gently teach your child what a food label is really saying—a skill that will benefit his or her health for a lifetime.

1. Visualize serving sizes.
Get out two or three packaged food items, preferably things that your child eats on a regular basis—cereal, oatmeal, applesauce—plus a measuring cup. Show her the serving-size number on the package label, and let her measure out a single serving. This visually reinforces serving sizes, the first number anyone should look at on a food label. Try it with a soda or juice bottle, too, which often say "2 servings."

One important note: Most nutritionlabels' serving sizes are based on a 2,000-calorie adult diet. For kids ages 4–8, portion sizes should be about two-thirds of an adult portion; for preteens, portions should be 80 percent to 90 percent of the adult amount, says Tara Dellolacono-Thies, RD, food coach for CLIF Kid.

2. Evaluate numbers.
Next, show kids numbers next to calories, fat, sugar, fiber, and cholesterol. When evaluating a packaged food for your elementary-school-age child, says Dellolacono-Thies, aim for 175 calories or less per serving; 1 gram or less saturated fat; no trans fats; no more than 13 grams added sugars; no more than 210 mg sodium; and at least 2 grams fiber. (Cholesterol alone is less of a risk factor for kids than saturated fat and sugar, she says, unless your child is on a specialized diet.) Added bonuses: Look for high percent Daily Values (DV%) for nutrients such as calcium, iron, zinc, and vitamin D, which most kids lack in sufficient quantities.

3. Compare and contrast.
Armed with these basic guidelines, compare, for example, the grams of sugar in a can of soda and a serving of cooked rolled oats, or the amount of calcium in a carton of milk versus a juice box. One-to-one evaluations will begin to give your child a sense of what numbers constitute a "high" or "low" amount.

4. Check the fine print.
"If you see artificial colors and flavors, artificial sweeteners, high-fructose corn syrup, or partially hydrogenated anything, those are good signs the food is of lower nutritional quality," says Dellolacono-Thies. Make it a game to see if kids can sound out items in the ingredient list. It's a classic teaching moment: Unpronounceable ingredients often mean it's a fake, lab-created "food." Then ask him to read the label on an apple. Surprise! No food label means it's a whole, real food—the best, most nutritious kind.

5. Translate knowledge into choices.
Once your child has gotten the hang of it, let her compare different food labels and have her choose which one she thinks is the healthier option. Plan a little extra time during your grocery shopping and try it there, too. With time and practice, she'll begin to incorporate the power of reading food labels before choosing food.

"Even when children walk up to a vending machine, where they can't read labels, you want them to know which is the healthier option," says Backer. "With label-reading practice, they'll become savvy shoppers who recognize healthy food options when they see them."