It’s hard trying to get teenagers to do anything they don’t want to do, like doing their homework or cleaning their rooms. We almost take it for granted that many of them don’t have good habits ingrained. But where do they stand when it comes to their eating and health habits?

A study released by the National Institutes of Health (NIH) and published in the Journal of Adolescent Health reveals that teens are not consuming enough fruits and vegetables and not getting enough physical activity.

The researchers at the Eunice Kennedy Shriver National Institute of Child Health and Human Development in Bethesda, Maryland followed 9,174 students, from 39 states, who were between the ages of 11 and 16. Questions about physical activity levels, frequency, and eating habits were asked, in addition to queries about time spent in front of a computer or electronic screen, weight control behavior, depression, body-image, general health, and life satisfaction.

“The students showed a surprising variability in eating patterns,” said lead author Dr. Ronald J. Iannotti. “But most — about 74 percent — did not have a healthy pattern.”

Based on their responses, the adolescents were categorized into three groups – typical, unhealthful, and healthful.

The typical group was the largest group, making up 47.2% of participants. They were least likely to exercise five or more days per week, and were equally unlikely to eat fruits and vegetables once per day. These adolescents spent more time engaging in screen-based activities (computer, television, video-games) than members of the healthful group, and while they did not indulge in sweets, junk food, or soft drinks frequently, they were most likely to be overweight or obese and have a negative body image.

The unhealthful group included 26.4% of participants, and they consumed the most sweets, junk food, and soft drinks, while engaging in little physical activity. Members of this group reported engaging in screen-based activities for more than two hours daily. And though they ate the most caloric foods, they were, surprisingly, more likely to be underweight. In addition, they experienced the poorest physical health, with depression symptoms, headaches, stomachaches, and dizziness.

The healthful group consisted of 26.5%, or a little over one-fourth, of the participants, and they engaged in the most physical activity of all three groups. More than two-thirds of students in this group exercised five or more times per week; these students also spent the least time engaging in screen-based activities. And instead of consuming sweets, junk food, and soft drinks, they were most likely to consume fruits and vegetables at least once daily. Predictably, they reported the best health, lowest rates of depression symptoms, and high rates of life satisfaction.

A similar study by a research team at the Centers for Disease Control looked at the eating and exercise habits of high school students. Of the 11,429 student-participants, 19% were found to be obese, and 17.8% were categorized as overweight.

While 60% of students reported taking part in physical activity for at least 60 minutes the day before the survey was taken, across all demographics, few teens got one hour or more of moderate or vigorous aerobic physical activity a day, including vigorous intensity physical activity at least three days a week, as recommended by the U.S. Department of Health and Human Services. Having a television in the bedroom and watching DVDs or videos further led to a lack of physical activity.

When it came to eating habits, many students skipped eating breakfast but ate lunch or dinner; however, those who did not skip meals were more likely to have a healthy weight and BMI. When eating dinner, those who ate with a TV on were linked to lower intakes of vegetables, calcium-rich foods, and grains, and with higher soft drink intake.

Teens were also found to be more likely to make healthy food choices when the options were available. Though male students were more likely than female students to have eaten fast food and French fries or other fried potatoes, the availability of fruits and vegetables at school or at home resulted in higher consumption of these healthy foods overall.

Altogether, the results of both studies show that “teens could stand to improve their health habits, whether walking or biking between home and school or eating more fresh produce each day,” according to Dr. Iannotti.

The Bottom Line

This news comes during the summertime – a time when children gain weight more quickly than they do during the school year. According to yet another study, this happens because “non-school environments are relatively unstructured and unsupervised, allowing children to indulge in sedentary activities and excessive snacking.”

The latest statistics reveal that almost 20% of 12 to 19 year olds are obese, so identifying the causes of obesity is important if we’re going to solve the obesity problem facing our nation’s youth. We’ve moved forward with the USDA’s Smart Snacks in School legislation limiting which snacks and beverages can be sold at schools, including in vending machines and on carts, but we’ve still got a long way to go.

But try as we might, research shows that lecturing or talking to our kids about healthful eating behaviors is simply ineffective. The bottom line is that the best thing parents can do is to live by example. Parents who exercise, prepare and serve healthy foods, and have a positive relationship with food, are likely to pass on these positive values to their children.

Remember, there are many places where we can effect positive change, but ultimately, healthful habits begin at home.