Grandparents are "giving abundantly" to financially support their grandchildren, "sometimes to the detriment of their own current and future financial security," according to a study by the MetLife Mature Market Institute.

The study said that 62 percent of grandparents provide such support–more than half of those had given more than $5,000 per grandchild over the prior five years, with the average amount exceeding $8,000.

Such financial support in many cases is "crucial" to the financial well-being of grandchildren, since the money most commonly goes for clothing, general support, and education ranging from day care to graduate school tuition.

"Forty-three percent report they are providing more financial support due to the economic downturn, and one-third (34%) are giving financial support to grandchildren even though they believe it is having a negative effect on their own financial security," the report said.

In addition, about a tenth provide regular care for grandchildren—a third of those providing babysitting type care five days a week and a six who are raising a grandchild.