http://developingchild.harvard.edu/key_concepts/toXic_stress_response...

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Q: What can we do to prevent damage from toXic stress response?

A: The most effective prevention is to reduce eXposure of young children to eXtremely stressful conditions, such as recurrent abuse, chronic neglect, caregiver mental illness or substance abuse, and/or violence or repeated conflict. Programs or services can remediate the conditions or provide stable, buffering relationships with adult caregivers. Research shows that, even under stressful conditions, supportive, responsive relationships with caring adults as early in life as possible can prevent or reverse the damaging effects of toXic stress response.

Q: When should we worry about toXic stress?

A: If at least one parent or caregiver is consistently engaged in a caring, supportive relationship with a young child, most stress responses will be positive or tolerable. For eXample, there is no evidence that, in a secure and stable home, allowing an infant to cry for 20 to 30 minutes while learning to sleep through the night will elicit a toXic stress response. However, there is ample evidence that chaotic or unstable circumstances, such as placing children in a succession of foster homes or displacement due to economic instability or a natural disaster, can result in a sustained, eXtreme activation of the stress response system. Stable, loving relationships can buffer against harmful effects by restoring stress response systems to “steady state.” When the stressors are severe and long-lasting and adult relationships are unresponsive or inconsistent, it’s important for families, friends, and communities to intervene with support, services, and programs that address the source of the stress and the lack of stabilizing relationships in order to protect the child from their damaging effects.

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in: http://developingchild.harvard.edu/key_concepts/toXic_stress_response