A new study of black and white Americans projects black individuals may have less family to lean on as they age. It also shows a continued increase in the number of Americans without living kin.

Why it matters: As we age, we tend to rely on children and spouses for help. An estimated 34.2 million Americans provided unpaid care to an adult age 50 or older in 2015, and 42% of caregivers are caring for a parent. They are, in other words, a pillar of health care in an aging America.

Key findings:

• Rachel Margolis from the University of Western Ontario and Ashton Verdery from Penn State University project 21.1 million black and white individuals over 50 will be without a living partner or children in 2060, an increase in step with population growth.
• When siblings and parents are included, the percentage of non-Hispanic whites age 50 and older without any close living kin will double by 2060. For non-Hispanic blacks, it will triple. "Together, we estimate that there will be 6.3 million whites and blacks without a living partner, children, siblings, or parents in 2060," they wrote.
• Biggest factors: An increase in childlessness, never marrying and mortality — "black Americans are twice as likely to lose a child or spouse by the age of 50," says Verdery, citing recent research.
• Limitation: There wasn't sufficient data to study other racial groups.

"Kinless-ness should be of interest to policy makers because it is more common among those with social, economic and health risks; those who live alone, with low levels of wealth, and disability," the researchers wrote.

Yes, but: The projection doesn't take into account, on the one hand, people who may have children but have become socially isolated from them, or the impact of incarceration. In that sense, the projection could be an underestimate of the family people interact with but it also doesn't factor in the other relationships people form and draw upon, especially individuals who know they won't be married or have children.

Kinless-ness therefore doesn't necessarily mean social isolation — or neediness, says the Urban Institute's Steven Martin, who points out that people in their 50s who never had children could have more resources and be relatively well-off in some respects.

"At least this gives us a baseline understanding of what direction this is headed," says Verdery.