is obese? >> it is tough to know. you know the kids are constantly growing. your kid may be chunky at one point and look fine because they had a growth spurt. go to cnn.com/health and we have a link in there. a great tool. you put in your child's height and gender and their age and they will tell you. >> you mentioned this is a study of mostly low income kids. the real risk and the trouble for parents is that sometimes the fastest, cheapest food is the worst food for your kids. here you are working hard trying to do the right thing and make sure your kid is getting three square meals a day and feeding him a lot of the things we were talking about, processed meats and processed foods which carry a lot of weight. >> it's awful in these neighborhoods produce is often more expensive than in wealthy neighborhoods which makes no sense whatsoever. but when you're faced with a choice and you don't have a lot of money and you can buy cheap, fast food or expensive produce you often will choose the cheaper stuff. >> the idea is get your kids moving more and feed them things