The government-backed survey of about 5,500 11- to 16- year-olds show that 53 per cent of the girls do not eat breakfast, one-third skip lunch and 17 per cent do not eat dinner.
The first survey, in 1986, found that 62 per cent ate breakfast, 84 per cent ate lunch and 89 per cent ate dinner.
The study, by Health Promotion Wales, is part of a wider European programme co-ordinated by the World Health Organisation. The latest report Diet and Young People in Wales, 1986-1992 shows that both boys and girls eat snacks more often.
The figure for boys snacking has risen from 28 per cent to 40 per cent in six years.