LONDON — What’s the difference between a McDonald’s Happy Meal and a box of Coco Pops?

Beyond the obvious, one can be advertised to children on British television, and the other cannot.

Britain’s Advertising Standards Authority ruled on Wednesday that the fast food giant McDonald’s could market its Happy Meal during children’s programs, but ordered Kellogg’s, which makes Coco Pops cereal, to remove commercials it had broadcast alongside a children’s show.

The decisions highlighted the British government’s increased scrutiny of fatty and sugary food and drinks being marketed to young people, part of a broader effort here to promote healthier eating among children.

Obesity affects nearly a third of children from 2 to 15 in Britain, and regulations prohibit the advertising of products that are high in fat, salt or sugar content during programs “commissioned for, principally directed at or likely to appeal to” children younger than 16.