Researchers sent people out to 250 fast-food eateries across the country. According to the study, only 6 to 8 percent were offered healthier alternatives to fries and burgers.
"The situation right now is it is possible to get a healthy meal at a fast-food restaurant, but it's very difficult," said Yale researcher Dr. Marlene Schwartz. "You have to go in, you have to know exactly what you're looking for, and you have to take the initiative to ask for it."
At a South Los Angeles McDonald's, ordering a Happy Meal, healthier choices other than fries and a soda were offered Monday.
Parents say it's sometimes tough to find healthier alternatives or find time to cook for their kids, so fast food becomes part of their diet.
"Sometimes McDonald's, they do offer the Apple Dippers," said Los Angeles resident Keisha Veal. "With my kids, I might let them have fries this time around, but then next time you have to get the Apple Dippers."
In a statement, McDonald's said: "We are proud of our menu and remain committed to offering our customers a wide variety of quality food and beverage choices that meet their dietary needs and tastes."
McDonald's and Burger King have joined what's called the Children's Food and Beverage Advertising Initiative. It's an effort to offer healthier foods to kids.
"You just want to pop something in the microwave or just go through a drive-through. That's just not the way we should raise our kids," said Glendale resident Charlene Hayrapet. "They should be able to eat healthier foods and just, as they're getting older, they need to understand what the difference is."
According to the study, the fast-food chains last year spent just over $4 billion on advertising aimed at children.