Over a 12 year period, nearly 6 of every 10 adult children age 51 or older will provide some care for an aging parent or in-law and nearly one in five will help an ailing spouse. And those who do are less likely to work, more likely to see a decline in their financial well-being, and more likely to fall into poverty, especially if they provide high levels of personal care for long periods of time.

According to a new Urban Institute study, adult sons spend an average of about 9 hours-a -week helping their frail parents with personal care while daughters spend about 12 hours. However, about 16 percent of sons and 24 percent of daughters spend more than 19 hours-a-week, or 1,000 hours-a-year, helping older parents.  The paper’s authors are my Urban colleague Barbara Butrica and Nadia Karamcheva (now at the Congressional Budget Office).

The researchers did not find that family caregiving reduced wages or hours of work by very much, after correcting for the parent’s health status. But it did conclude that caregivers—especially men– were less likely to work at all than comparable adults who were not helping parents or spouses.

Building on the results of a national survey of older Americans called the Health and Retirement Study, the research followed people from 1996 to 2010. Participants are surveyed every two years.

The Urban study looked those adults 51 and older who helped with household chores such as cooking, cleaning, and transportation, as well as those who provided more intense personal assistance with tasks such as dressing, eating, and bathing.

It found that, in any given two-year period, about one-third of adult children with living parents or in-laws provided them some assistance while about 7 percent helped their own spouses.

As many other surveys have shown, women were more likely to care for frail elders than men. About 42 percent of daughters were helping parents or in-laws in poor health, while only about 30 percent of sons were assisting frail parents. Sons were much more likely to help with chores such as shopping and cleaning than with personal care such as bathing or dressing.

But while one-third of adult children cared for parents in any two year period, many more were likely to do so over the full 12-years. Fifty-seven percent of adult children age 51 or older cared for a parent or in-law at some time during that period.

I asked Barbara how long an adult child can expect to care for a parent. On average: about 3.5 years, although some of that time may be helping only with household chores. Typically, adult children provide more intensive personal care for about 2.5 years.

How does caregiving affect an adult child’s career and financial future? That’s been an ongoing debate for decades. Like other researchers, Barbara and Nadia found that caregivers are less likely to work, and if they are employed, are more likely to work part time or for fewer hours, and be paid lower wages. But when they corrected for parental health, they found little difference in hours worked or pay between caregivers and non-caregivers.

However, they also found that those adult children caring for frail parents were significantly less likely to work at all than similar adults who were not assisting frail elders, especially if those caregivers were providing intensive assistance.

For instance, 57 percent of men who assist their parents also work, while about 72 percent of those who are not caregivers are employed. In other words, you are significantly less likely to be holding down a job if you are also helping a parent. And that’s especially true for men.

The impact on work is also dramatic when it comes to men caring for a spouse. Husbands providing heavy levels of help are almost 10 percentage points less likely to have a job than those who are not caregivers.

The economic consequences of less work are pretty straightforward. The longer adult children care for a parent and the more intense that care, the less their financial wealth will grow, and the more likely they will fall into poverty. The consequences are similar for those caring for spouses.

Other studies have looked at the physical and emotional cost of family caregiving. This one focuses on the financial price. And while the results are not as dramatic as other studies, it shows that whatever else family caregiving is, it is not free.