One-in-five children in Ireland reported going to school in the morning or to bed at night hungry in 2010, because there was not enough food at home. The Health Behavior in School-aged Children Survey 2010 is conducted in collaboration with the World Health Organization Regional Office for Europe carried out every four years, with 43 countries and regions participating in 2010. A total of 16,060 children ages 9-18 from 256 schools in Ireland participated in the survey. Twenty-one percent said they had gone to bed or gone to school hungry, compared to 17 percent of children in the survey published six years ago, The Irish Times reported. Children who were younger and children who were poor were more likely to have gone hungry. The survey found 51 percent said they exercised four or more times a week, down from 53 percent in 2006. More than 25 percent of those ages 15-17 reported having had sex. Of those who reported having had sex, 93 percent said they had used a condom, while 59 percent said they used a birth control pill. Those who said they currently smoked fell from 15 percent six years ago to 12 percent last year, but children who said they had ever smoked dropped from 36 percent to 27 percent over the same period. Forty-six percent of children reported ever drinking compared with 53 percent in 2006, while those who reported using marijuana in the past 30 days dropped from 7 percent in 2006 to 5 percent in 2010.