When Harry Houdini did tricks with a wink - and then donned a hood - it was entertaining. But when junk-food conglomerates hoodwink kids into eating food that's not good for them, well, that's a piece of marketing magic that's definitely not entertaining.

It's a problem that's gone viral.

These days, hundreds of millions of dollars are spent on cleverly packaged ads for junk food. They're served up on websites, Twitter, Facebook and other social-media platforms and reach your kids through their computers, cellphones and tablets.

The latest? Super-sweet cereal brands have launched online advergames. These digital amusements may seem entertaining, but really they're insidious ways to get kids hooked on products filled with added sugars and additives. Take a look at advergames.com if you think we're kidding.

That's why we're on a campaign to get you - Mom and Dad - to help your kids stay healthy by learning to resist junk-food marketing that targets them! Talk to your kids about the sneaky and deceptive ads that target them. Make them aware of the ads' power to cultivate a "gotta have that" feeling that's in their worst interest.

Create your own game: Make your child a "try to pull the wool over your eyes ad" detective and reward him or her for spotting them.

Take the TV out of their bedroom. Unsupervised viewing erases your ability to help your child evaluate what he or she is seeing.

Establish times to play outside and set strict limits on time spent on digital devices and computers, except for studying.