Exactly why women's lack of relative contacts didn't affect their well-being wasn't examined in the study, Cable said.
However, she said, ''it has been said that women are less likely to draw psychological resource out of their kinship." Relatives often put pressure on women, she said, ''whereas friends are more likely to support women's own choices."
The findings square with previous research, said Dr. Lydia Li, an associate professor of social work at the University of Michigan, Ann Arbor, who has studied social interaction and well-being.
The finding about family contacts being more important for men than women makes perfect sense to her. "While larger kinship network should have positive effects for both men and women, the traditional role of women as support providers in kinship, which is obligatory in nature, may lead to their personal resources [being] more depleted," she said.
To rule out the possibility that the people with no friends or family contacts were ill-adjusted to begin with, Cable took into account the mental health status of the men and women at age 42.
She found a link between the friendship and family networks and well-being, but not a cause-and-effect.
Advice for midlife men and women? Cable said her research shows that friends are important for both men and women to boost well-being at midlife, but that men should pay close attention also to their family contacts.
"Middle-aged people often have to cope with multiple demands and have limited time for themselves," Li said. "But it is worthwhile to spare time and effort to expand and nurture relationships. For women in particular, friendship is a good investment."
To learn about work friendships, visit the American Psychological Association.
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