The number of teens getting enough sleep, nutritious food and exercise is dropping. Girls are faring the worst.

Teenage girls sleep less, move less and eat fewer key nutrients than a decade ago, according to a recently published report from the Centers for Disease Control and Prevention that highlights health and behavior trends in U.S. high school students.

The report, which is part of the Youth Risk Behavior Surveillance System (YRBSS), comes two years after the CDC released mental health data showing U.S. teen girls were experiencing record levels of persistent sadness, violence and suicide risk.

While the cause for these declining trends in girls’ health is not entirely clear, Dr. Lonna Gordon, chief of adolescent medicine for Nemours Children’s Health in Orlando, Fla., tells Yahoo Life that teens today “have less … space to consider what is needed to grow, experiment and succeed. [They] live in an increasingly competitive world and, thus, lead very isolated lives. They are over-scheduled.”

Kaylee Brown, a 16-year-old high school student in Texas, puts it more bluntly: “I feel like my generation is far less healthy than generations before, because we just eat what we want, tend to be lazy and are addicted to phones.”

Here's what the report says about what teen girls can do to take better care of themselves — and why it matters.

Sleep

Only 22% of female students in 2023 reported getting at least the recommended eight hours of sleep on a typical school night, down from 29% in 2013.

Screen time is linked to “a host of insomnia symptoms in teenagers,” according to the Sleep Foundation. While Brown says she monitors her screen time to ensure it doesn’t affect her sleep, “stress over school is the biggest thing” that keeps her up at night.

Girls tend to be more biologically sensitive to stress than boys, Leah Kaylor, a licensed clinical and prescribing psychologist, tells Yahoo Life. And “teen girls [also] tend to ruminate more than boys, which can delay their ability to fall asleep," she says.

“The significant hormonal shifts during puberty … directly [impact] sleep quality, circadian rhythms and energy levels,” Kaylor adds.

Research shows that teenagers who get the recommended eight to 10 hours of sleep have better focus, mood regulation and overall physical health. On the flip side, lack of adequate sleep is linked to anxiety, depression, recklessness and poor decision-making.

Consistent routines, especially sticking to bedtimes and wake times, is one way to improve teens' well-being, says Gordon. “Studies show that teens who are well-rested and emotionally regulated are better equipped to make healthy food choices.”

Nutrition

To assess healthy food choices and diet behaviors, the survey tracked how often students ate breakfast daily and drank plain water daily, as well as whether they ate fruits and vegetables every day and avoided soda and sports drinks. According to the survey results, only 22% of girls ate breakfast daily in 2023, down from 34% in 2013. And 52% percent of girls ate fruit every day, down from 60% in 2013.

In a bit of good news, the data showed that more teens are avoiding soda and sports drinks than in past years, particularly female students. And from 2021 to 2023, the percentage of high school students who ate fruit daily increased. About half of girls reported drinking plain water at least three times a day, a slight increase from 48% in 2015, when the question was added to the survey.

But overall, teen girls are falling short when it comes to nutrition. “We live in a culture of instant gratification, so it’s satisfying to eat foods that make our brains feel good right away,” says Brown. “My biggest challenge to eating healthy is time.”

Gordon agrees that many teenagers are over-scheduled, which can make it difficult “to prioritize what is truly important.”

Shelley Balls, a registered dietitian and nutritionist for Consumer Health Digest, says misinformation on social media may also play a role in poor eating habits. There’s “peer pressure to look a certain way, which typically can involve disordered eating habits.”

In a review published in 2014 in the American Journal of Public Health, researchers observed a “significant” link between unhealthy eating and poorer mental health in adolescents. They also saw a “consistent” connection between a nutritious diet and better mental health.

With U.S. students eating up to half of their daily calories in school, the authors of the new CDC report encourage schools to create policies around nutritious school foods. This could include free school meals for all students regardless of family income level, along with nutrition training for school staff.

Physical activity

Overall, there was a drop from 2013 to 2023 in the percentage of high school students who reported being regularly physically active. Report authors say this is especially "concerning" in the case of girls.

That’s because only one in five girls got at least one hour of daily physical activity, and one in four reported having physical education every day. A higher percentage of boys than girls reported regularly strengthening their muscles, participating on a sports team and meeting both aerobic and muscle-strengthening recommendations.

An orthopedic physical therapist, Milica McDowell, tells Yahoo Life that increasing academic pressure may be one reason why high schoolers are less physically active today than even 10 years ago. Another potential reason: smartphones.

In 2023, more than 90% of teens had access to smartphones, a “huge” jump from even the 2010s, McDowell notes. “The prevalent use of smartphones in lower age demographics has created a shift in how kids prefer to spend leisure time.”

Kaylee Brown’s mother, Jena Brown, is a sports dietitian and owner of Victorem Performance Nutrition. She also believes smartphones have changed how this generation is growing up. “I see my daughter and her female peers facing a lot more ‘noise’ than when I was a teenager," she tells Yahoo Life.

One easy way teens can reduce the noise and work more exercise into their day is simply to go out for regular walks, experts say. Walking with family members, in particular, “has been shown to improve communication and positive feelings between parents and kids,” says McDowell. “[It] doesn't take any specialized training or equipment and can be done without having much pre-planning required.”

Ultimately, the balance of sleep, nutrition and exercise — “a dynamic system which works together to promote optimal health” — is particularly unique for teenage girls because of the societal pressure, hormonal fluctuations and cultural expectations they experience daily, says Amy Shapiro, lead nutritionist at ButcherBox. “It is important to instill and share strategies during adolescence to build a solid foundation for physical and emotional health, to empower teenage girls during their formative years and to set up healthy habits in the years that follow.”