Researchers at the University of Chicago watched nearly 100,000 30-second advertisements for food products including breakfast cereals, snacks, sweets and drinks, that were aired on television during programs watched by 2- to 17-year-olds.
The long-term study showed that 97.8 percent of the food product ads seen by children aged between two and 11 were high in fat, sugar and sodium, or salt.
The older, 12- to-17-year-old age group fared only marginally better, with nearly 90 percent of ads targeting them for foods of poor nutritional quality, says the study, which was published in the Pediatrics scientific journal.
Nearly half the ads targeting both age groups, which watched an average of three hours and 19 minutes of television per day, were for products that were high in sugar. Nearly all the breakfast cereal advertisements for pre-teen children were for high-sugar products.
'Exposure to food advertising significantly influences children's food preferences/choices, food intake, and product-specific food purchase requests among young children,' the study said.
Researchers at Stanford University reported the results of a study last month that showed that food tastes better to American three- to five-year-olds if it carries the Golden Arches logo of the McDonald's fast-food chain.
The authors of that study pointed out that McDonald's spends more than one billion dollars a year on advertising in the United States.
The University of Chicago study was undertaken 'in the light of the high rates of child and adolescent obesity' in the United States.
Childhood obesity increased more than three-fold in the United States between 1978 and 2004, a study published last month showed.
'Today's children are likely to be the first generation to live shorter, less healthy lives than their parents. Approximately 25 million children are already obese or overweight,' the Trust for America's Health (TFAH) said in its fourth annual 'F as in Fat' report.