(PhysOrg.com) -- Most Americans live within 25 miles of their mothers, according to a report issued by the University of Michigan Retirement Research Center.
The study calls into question a widespread belief that when children grow up, they're likely to move far away and not be on hand to help out when their mothers get older.
The analysis is based on a nationally representative sample of married and single adults age 25 and over from the National Survey of Family Health and on data from the U.S. Census.
The probability that individuals live close to their mothers is strongly related to education, according to researchers Janice Compton and Robert Pollak, who conducted the analysis for the U-M Retirement Research Center, part of the U-M Institute for Social Research (ISR).
"Adult children with college degrees are much less likely to live with or near their mothers," said Pollak, who co-authored a working paper titled "Proximity and Coresidence of Adult Children and their Parents: Description and Correlates."
For example, among couples who both have college degrees, about 50 percent live more than 30 miles from both their mothers and only 18 percent live within 30 miles of both mothers.
Among couples who have no college degree, the situation is reversed: about 19 percent live more than 30 miles from both their mothers and 50 percent live within 30 miles of both their mothers.
"If you go to college, you're more likely to work away from the place you grew up," Compton said. "Plus, you're more likely to marry someone who's not from your hometown and or even from your state. And since your mothers don't live in the same area, you are less likely to move to be close to one mother but not the other."
Unmarried adults tend to live closer to their mothers—about 15 miles compared to about 25 to 30 miles for married adults.
Compared with whites, Hispanics are no more likely to live in close proximity to their mothers, but they are twice as likely to live with their mothers. Blacks are more likely than whites to live near their mothers and also more likely to live with their mothers.
"There are certainly cultural issues that affect coresidence and family proximity," Pollak said.
Gender has no impact on proximity. But it is strongly linked with coresidence, the researchers found. "When we separate our sample by marital status, we find that married women are more likely than married men to live with their mothers while unmarried women are less likely than unmarried men to live with their mothers.
Younger adult children are more likely, and older adult children are less likely, to live with or near mom. Only children live closer to their mothers, on average, but for those children who have siblings, the researchers found no birth order effect. In other words, the youngest in the family were no more likely to live close to mom than were the first-borns.
The researchers also analyzed how proximity patterns were influenced by the needs of older mothers for help or the needs of adult children for help with childcare. Adult children are more likely to live with their mothers when one of them needs help—when mothers are older or in poor health, or when adult children are unemployed or unmarried. But the probability of close proximity depends primarily on the age and education of the adult child, not the mother's need for care.
"What's striking about the data is how seldom married couples live with either his mom or her mom," Pollak said. "But almost 20 percent of single men live with their mothers. And if you exclude those who are living together, the median distance of single men to their mother's home is 15 miles.
"It would be interesting to know how many of the single men have never left home, which puts a different twist on the question of who's taking care of whom."
Pollak is an economist at Washington University in St. Louis, and Compton is an economist at the University of Manitoba.
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More information: Paper: www.mrrc.isr.umich.edu/publications/papers/pdf/wp215.pdf