Skipping breakfast before a day of school significantly reduced students' speed and accuracy on cognitive and memory tests compared with those who ate breakfast, according to a study recently published online in the journal Appetite.

Researchers compared the performance of 1,386 students from 32 schools throughout the U.K. on several Internet-based tests of attention, memory and reaction time. Subjects included 721 girls and 665 boys age 6 to 16 who logged onto a website between 7:42 a.m. and 12:33 p.m. On testing day, 1,202...