A loving mother who kisses her child's boo-boos may be providing more health benefits than she knows.
New research indicates that early childhood experiences can have a lasting effect on health by influencing a person's risk for chronic inflammation, the immune reaction that is the body's first line of defense against disease.
"We already know inflammation is a big determinant of disease, and now we're asking, what are the determinants of inflammation," said study researcher Steven Cole, a molecular biologist at the University of California, Los Angeles.
Bond with mom
The researchers took blood samples from 53 adults who grew up in households of low socioeconomics status (SES). Half of the subjects reported having relatively close, loving relationships with their mothers growing up, while the other half had cooler, more distant relationships with their mothers.
Subjects who had a warm bond with mom expressed fewer genetic markers of inflammation, which over time can take a toll on the body. Genetic markers are molecules that indicate a gene is being actively turned into protein, in this case proteins that contribute to inflammation.
Prior studies have linked low SES with chronic inflammation and with chronic disease. So if the new findings are true, a close relationship with mom may be especially important in stressful environments.
The finding, published online May 18 in Molecular Psychiatry, fits with data indicating that close family ties can protect children against some of the negative consequences of growing up in poor homes.
"Even bad circumstances can be overridden by good parenting," Cole said. "That lasts for decades and it gets all the way down to your genes."
Inflammation and disease
Inflammatory proteins are necessary during an infection to tell the immune system and other cells of the body to beef up defenses. But when people are stressed out, their bodies may fail to switch off inflammation.
"These things are great for healing injured tissue, but they're not so good if they're on long term," Cole said. "You really want them to be on where and when you need them and off the rest of the time."
Chronic inflammation is linked to a number of conditions, including cardiovascular disease, diabetes, depression and cancer. Cole compared inflammation to a "fertilizer" that feeds disease. For example, in women who have been successfully treated for breast cancer, those who show high levels of inflammation have twice the risk of a recurrence of the cancer, research has shown.
Early life experiences can lead to the release of hormones that channel the body into being more or less prone to chronic inflammation, Cole said.
Harsh family life
In another recent study, published online April 29 in Psychological Science, researchers found that adolescent girls who reported having harsh family lives growing up – abusive, neglectful or violent – had increasing markers of inflammation during the 18-month study period compared with girls who came from more stable homes.
Neither an abusive home nor a cool relationship with mom automatically translates into disease later on in life, however. Cole said early family experiences are one factor that shapes the way the body responds to stress. From his research, Cole hopes to develop a checklist of risk factors, including family upbringing, that can guide treatment decisions.
"It's nice to know that despite low SES there are things that can help buffer us," said Mary-Frances O'Connor, a clinical psychologist at the University of California, Los Angeles, who was not involved in the new studies. Other close relationships, and not just the mother-child bond, might have a similar protective effect, she said.
O'Connor also noted that low SES affects inflammation through the stress hormone cortisol but maternal warmth appears to operate through other molecules that are important to the inflammatory response.
"That may impact how we treat you in the future," she said, if researchers are able to develop drugs that work on inflammation in different ways.
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