LOS ANGELES — Have food and beverage commercials aimed at kids gotten better since companies like Kellogg's, Nestle, Coca-Cola Co. and McDonald's Corp. pledged to cut back on ads featuring unhealthy fare? It depends on how you define "better," a new study finds.

Food and drink advertising on TV is big business, adding up to about $745 million each year, according to the study published Monday in the Archives of Pediatrics and Adolescent Medicine. More than half of those dollars are spent trying to reach kids younger than 12. Those ads work: Other studies have shown that as kids are exposed to a greater number of enticing commercials for sugary drinks, salty snacks and meals cooked in deep fryers, the heavier they get.

So a group of researchers from the University of Illinois in Chicago hunkered down with TV ratings data from Nielsen Media Research. They found that the total number of food-related ads seen by kids has indeed dropped since the implementation of the Children's Food and Beverage Advertising Initiative (CFBAI), which was launched in 2006 by 17 companies in an act of self-regulation.

In 2009, kids between age 2 and 5 saw an average of 10.9 such commercials per day, down 18 percent from 2003, the researchers calculated. Meanwhile, kids between age 6 and 11 were exposed to an average of 12.7 food-related commercials each day in 2009, a 7 percent drop compared with 2003.

Most of the food and drink ads — a full 86 percent of them — featured products high in saturated fat, sugar or salt. Among commercials for "snacks," a whopping 97 percent were high in at least one of these unhealthy ingredients (usually salt). But those figures from 2009 were actually an improvement compared with 2003, when 94 percent of all food and drink commercials were high in saturated fat, sugar or salt.

One category of food advertising for kids has increased since the advertising initiative went into effect — commercials for fast-food restaurants. Between 2003 and 2009, exposure to such commercials increased by 21 percent for the younger children and by 31 percent for the older kids.

The 17 companies that are part of Children's Food and Beverage Advertising Initiative account for roughly 80 percent of the food and drink commercials seen by kids, and 88 percent of those ads were for unhealthy foods, the study found. That may not sound like a huge improvement, but these companies dialed back their kid-focused ads more than the companies that weren't part of the initiative.