As seniors enter retirement, many of them are bringing theirmortgages right along with them — despite the fact that home equityis on the rise.

Related: Americans worry they will outlive theirsavings

According to data from the National Reverse Mortgage LendersAssociation, U.S. homeowners aged 62 and older are holding morethan $6 trillion in equity, an increase of $164.9 billion in homeequity from the last quarter of 2015.

But along with that increase in home equity comes a $4.9 billionincrease in mortgage debt held by that age group.

The Federal Reserve says that 6 in 10 adults in their 60s andalmost 4 in 10 of adults age 70 and older owe money on theirmortgages, in its 2013 study "Insights into the Financial Experiences of OlderAdults." However, this isn't always a sign of financial stress,it points out. Some retirees prefer to pay down a lower mortgage inmonthly payments that better fit their budget rather than pay itoff in a lump sum.

But adults 65 and over also owe more on their mortgage than thatcohort did a decade before, says the Consumer Financial ProtectionBureau. From 2001 to 2011, the median amount owed by olderhomeowners on mortgages increased from around $43,000 to almost$80,000 according to the CFPB's Office on Older Americans in itsMay 2014 paper "Snapshot of older consumers and mortgagedebt."

The toll taken by the Great Recession on people’s finances — notto mention their psyches — has led to a quest, for many, for asource of lifetime income to see them through retirement. For some,that has meant seeking out a reverse mortgage — now gainingtraction as a retirement income tool.

The U.S. government insures only one type of reverse mortgage,through Federal Housing Administration-approved lenders. It’scalled a Home Equity Conversion Mortgage, or a reversemortgage.

About half of those seeking a reverse mortgage use some of theirloan proceeds to pay off an existing mortgage, according toresearch from Stephanie Moulton, a professor at the John GlennSchool of Public Affairs at the Ohio State University.

Others use the money to supplement retirement income or to helpthem cope with an unexpected medical or other expense, or even justto help them remain in the house they’re comfortable in — and whilereverse mortgages can prove useful for all these things, they’renot without caveats.

Not only do most seniors not understand them, but there aredefinite drawbacks that can affect seniors in ways they might notanticipate.

In a report on reverse mortgages, Rep. Mark Takano,D-California, warned of a number of those drawbacks, including highcosts that can come along with the loan; the death of a spouseresulting in the surviving spouse losing the home; and the dangerof the loan going into default — which can occur if the homeownerfails to keep up the property or pay homeowner’s insurance andproperty taxes.