BETHESDA, Md. – Only half of American youths are getting the recommended amount of exercise and less than one-third are eating the suggested amount of fruits and vegetables each day, according to researchers at the National Institutes of Health. 

In a survey of youth in 39 states, NIH researchers questioned nearly 10,000 students between 11 and 16 years old about their activity levels and eating habits. They also asked the students to describe their emotional health, body image and general satisfaction with life.

“The students showed a surprising variability in eating patterns,” said lead author Ronald J. Iannotti, Ph.D., of the Prevention Research Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), the NIH Institute in which the study was conducted. “But most — about 74% — did not have a healthy pattern.”

The researchers found that the adolescents’ diet and activity habits could be classified into three general categories. They described the first group as unhealthful. This group accounted for 26% of participants. The second group, classified as healthful, accounted for 27%. Because it was the largest group — including 47% of participants — the researchers classified the third group as typical. 

The researchers surveyed participants about: their daily amount of physical activity, the amount of time they spent in front of a computer screen or other electronic screen, and the amount of healthy and unhealthy foods they consumed. Other questions sought information on symptoms of depression and self-satisfaction with their bodies.

The analysis of the survey results showed that the typical youth were least likely to exercise five or more days each week or to eat fruits and vegetables at least once a day. They were more likely to spend time watching television, playing video games or on a computer than the healthful group, and less likely to do so than the unhealthful group. They infrequently ate fruits and vegetables but also infrequently ate sweets, chips or fries, or had soft drinks. Youth in this group were more likely than youth in the other two groups to be overweight or obese and to be dissatisfied with the appearance of their bodies.

The unhealthful group consumed the most sweets, chips, French fries, and soft drinks. They also were more likely than the other groups to report watching TV, playing video games and using a computer more than two hours a day. Despite the caloric foods they consumed, youth in the unhealthful group were more likely to be underweight and to report needing to put on weight. Youth in this group also were more likely to report symptoms of depression and of poor physical health, such as backaches, stomachaches, headaches or feeling dizzy.

Nearly 65% of students in the group that the researchers termed healthful reported exercising five or more days per week — the highest rate of the three groups. These students were least likely to spend time in front of a screen and were most likely to report eating fruits and vegetables at least once a day. Students in this group also were least likely to consume sweets, soft drinks, chips and French fries. They reported the lowest rates of depressive symptoms and the highest life satisfaction ratings.

All three groups could stand to improve their health habits, Dr. Iannotti said, whether walking or biking between home and school or eating more fresh produce each day.

According to the U.S. Department of Health and Human Services’ Physical Activity Guidelines for Americans, children and adolescents should get one hour or more of moderate or vigorous aerobic physical activity a day, including vigorous intensity physical activity at least three days a week.