stress while they are growing up that one researcher says could stay with them into adulthood.
Related: Can kids "catch" your stress?
"If a child has a pervasive sense of adversity in his or her childhood for whatever reason, the brain responds to that kind of hardship by becoming more sensitized to stress," Dr. Rajita Sinha, director of the Yale Stress Center, recently explained to CNN.
The brain becomes hard-wired to react more strongly, she says, making that person more likely to have a greater reaction to stress than people who do not have a similar history.
What childhood stress is so big that is burrows into the brains for decades? Research points to pain, illness, and injury as major stressors for kids. But a child's stress level can increase to "severe" during family conflicts such as divorce, abuse, witnessing violence, financial crisis, the death of a loved one, or a parent who suffers from addiction or mental health problems.
While anxiety is a normal reaction to stress and can even be OK for children to navigate, according to the National Institute of Mental Health, some people experience excessive levels of anxiety. One in eight children are affected by an anxiety disorder, according to the Anxiety Disorders Association of America, including those who are deemed to have post-traumatic stress disorder.
While humans are "adaptive animals," Sinha says many children are experiencing stress before their ability to deal with it is completely developed. The adversity in their young lives therefore leads to a higher overall stress level into adulthood.
"The stress pathway is developing during childhood. The stress system needs time to grow and become fully functional," Sinha says.
Small children under stress are sources of concern, according to her studies. But she also sees adolescents, who are more likely to self-isolate, as particularly vulnerable. Teenagers' stress symptoms may range from sleep difficulty to overeating to school truancy to taking pain medication unnecessarily.
While parents may not be able to completely shield children from stressors -- a kid's home life might be magical but they may encounter a bully in Sunday school or suddenly lose a grandparent to cancer -- Sinha says parents, teachers, and caregivers can help build resistance and optimism when kids experience stress.
"Things happen. Families will face adversities. But if parents, teachers, and other adults are helping to guide children by talking about the trauma and providing them with adaptive skills, then those children will be more inclined toward protection and resilience, as opposed to risk."
How can we help protect our kids from becoming over-stressed adults?
1. Seek social support. Sinha says that interacting with others and garnering family support is a primary way we can protect kids from the risks of stress.
2. Embrace education and intellectual challenges. Children are more likely to learn to navigate tough stuff if they are challenged in a safe environment like school, she reports. Teachers that encourage students to think abstractly, for example, are helping their brain develop in ways that will serve stressed children in the moment and, perhaps, in the long term.
3. Develop optimism and tactics to control emotions. Parents and other adults who are active in a child's life may be able to help protect kids from carrying stress forward in such significant ways. A University of Wisconsin-Madison study revealed that a mother's voice, whether during a conversation or phone call or whisper during a hug, can produce significant biochemical responses that soothe stressed children. Another study of 405 inner-city children showed that yoga instruction boosted the kids' self-esteem and grades and decreased behavioral problems associated with the stress of poverty in South Central Los Angeles. Getting enough sleep consistently has also been shown to help children deal with stress more effectively. Some even say a little playful, safe roughhousing can do kids (and parents) a world of good.
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