Do you try to negotiate with your kids to get them to eat their vegetables? (One Brussels sprout, 10 more minutes of TV time.) Or do you promise dessert if they eat their salad? That's hit or miss, at best, and then you have to fret about whether the dessert is healthy or not.

But it turns out the most effective way to get kids to eat more vegetables and fruit is to put more on their plates.  

Researchers from the Laboratory for the Study of Human Ingestive Behavior at Penn State tested two strategies for encouraging kids to eat more fruits and vegetables. One group of kids had 50% more added to fruit and vegetable side dishes in daily meals. A second group had 50% more fruits and vegetables substituted for an equivalent weight of other foods. For example, when researchers added a couple of extra ounces of veggies to lunch, they subtracted a couple of ounces of mac and cheese.

Both strategies work. Adding more fruit and vegetable side dishes boosted kids' intake of veggies by 24% and fruit by 33%; substituting fruits and veggies for some of the other foods increased veggie consumption by an astounding 41%, fruit by 38%.

And while you're tricking your kids, you can trick yourself too. Only 9% of adults eat the recommended amount of vegetables; 12% get enough fruit.