They're telling us what to eat and how much of it.

McDonalds announced that they are changing the venerable Happy Meal - adding a serving of fruit or vegatables...and shrinking the size of the fries.

Under pressure from health and children's advocacy groups, McDonald's Corp. is making changes to its famed Happy Meals.

The changes, to be announced Tuesday, will take effect in September in some markets and then roll out to all 14,000 McDonald's restaurants in the U.S. by April.

So what's changing specifically?