Two studies released this week reveal how common problems facing children, namely stress and obesity, can have lasting effects throughout their lifetimes. One of the study authors called the findings “a wake up call” for parents, teachers, physicians, and others responsible for children’s health and well-being.

The research—out of Johns Hopkins and UCLA—may change the way we view childhood illnesses, from learning disabilities and asthma to schizophrenia and severe depression.

The Effects of Stress on Mental Illness

Researchers at Johns Hopkins say they’ve found yet another reason to provide preventative care for teens predisposed to mental illness.

“We have discovered a mechanism for how environmental factors, such as stress hormones, can affect the brain's physiology and bring about mental illness,” study leader Akira Sawa, M.D., Ph.D., a professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine, said in a press release. Sawa's study was published in the latest issue of Science.

In controlled experiments using mice, researchers claim to have determined how elevated levels of stress hormones can bring out mental illness in children with a family history of mental disorders.

The research team isolated mice for a three-week period during their adolescence. Healthy mice showed no noticeable difference in their behavior, but mice known to have characteristics of mental illness did not fare so well. During isolation, these mice showed signs of mental illness, such as hyperactivity. When put in water, these mice failed to swim, an indicator of depression, and they continued to behave abnormally when returned to the company of other mice.

These results led scientists to conclude that stressors during childhood carry over into adulthood. Upon further investigation, the “mentally ill” mice showed elevated levels of cortisol, a stress hormone released when the body is in fight-or-flight mode. The mice also appeared to have lower levels of dopamine in the part of the brain associated with higher functioning. Prior research has shown that changing levels of dopamine appear in humans with depression, schizophrenia, and other mood disorders.

When given a compound that affects cortisol—RU486, which is also used in cases of hard-to-treat psychotic depression and for emergency contraception—all symptoms in the abnormal mice vanished. Researchers hypothesized that the stress of isolation during adolescence had altered the mice’s genes associated with cortisol production.

More studies are required to fully explore the impact of early childhood trauma on the adult brain, but researchers say that preventative measures should be taken for children with a family history of mental illness.

The preventative measures, Sawa said, include protecting vulnerable teens from social stressors, such as neglect.

Earlier this week, research from a Swiss think-tank confirmed that a child’s mind physically changes when exposed to violence at a young age. It can have lasting effects on the part of the brain associated with decision-making, addiction, and learning social cues.

Read “Youth, Violence, and the Structure of the Brain.”

Obesity & Learning Disabilities

Researchers at the University of California, Los Angeles also noticed a trend: as childhood obesity rose dramatically over the past two decades so did other conditions that typically begin in childhood, such as ADHD, asthma, and learning disabilities.

The research team conducted the first national profile examining weight and 21 indicators of general health using data on more than 43,000 children ages 10 to 17. They found that the 15 percent of children they studied who were considered overweight and the 16 percent who were considered obese were more likely to have:

  • poor overall health
  • greater disability
  • a greater tendency toward emotional and behavioral problems
  • higher rates of grade repetition
  • missed school days and other school problems
  • ADHD
  • conduct disorder
  • depression
  • learning disabilities
  • developmental delays
  • bone, joint, and muscle problems
  • asthma
  • allergies
  • headaches
  • ear infections

"This study paints a comprehensive picture of childhood obesity, and we were surprised to see just how many conditions were associated with childhood obesity," Dr. Neal Halfon, lead author and professor of pediatrics, public health, and public policy at UCLA, said. Halfon's analysis controlled for sociodemographic factors, such as race and family income level.

Halfon added that the findings should serve as “a wake-up call” about the health risks posed by obesity so that parents, doctors, and others can intervene early.

Why the Cycle of Obesity Continues

Obesity and other health problems are still a chicken-and-egg argument. The UCLA team said that cause-and-effect relationships shouldn’t be drawn from their study, and that further research is needed to determine which comes first, obesity or poor general health.

They speculate that the rise in chronic childhood conditions is related to decades of changes in the social and physical environments in which children live, learn, and play.

"Obesity might be causing the co-morbidity, or perhaps the co-morbidity is causing obesity—or both might be caused by some other, unmeasured third factor," Halfon said.

The study does however highlight serious health effects facing a growing segment of U.S. children.

According to the Centers for Disease Control, 17 percent of children ages 2 to 19 are considered obese, a rate that’s tripled since 1980. That equates to 12.5 million children.

They propose that obesity-prevention efforts target these social and environmental influences, and that overweight kids should be screened and managed for a range of co-morbid conditions.

How to Reduce Your Child's Stress & Weight

The troubling thing, researchers in both study groups noted, is that stress is a major contributing factor for mental and physical illness.

In fact, chronic stress—from childhood to adulthood—has been linked to many health conditions and can drastically reduce not only your quality of life but also the length of your life.

One of the best ways to reduce stress and your waistline is to get regular exercise. The recommended amount for adults is 2 ½ hours per week.

Besides regular exercise, parents and children can both reduce the stress in their lives by:

  • eating a balanced diet
  • staying hydrated
  • finding appropriate coping mechanisms, such as hobbies
  • doing relaxation exercises, such as deep breathing or meditation
  • effectively communicating about their feelings
  • practicing time management skills
  • getting adequate sleep every night

Learn more simple ways to reduce your stress.

More Resources

  • Understanding Schizophrenia
  • Famous Faces of Schizophrenia
  • Recognizing Depression Symptoms
  • 7 Signs of ADHD
  • Stress Management
  • 7 Healthy Lunch Ideas for Kids
  • Tips for Sleeping Better
  • Creative Ways to Burn Calories