In spite of decades of advice to the contrary and an improving economy, millions of Americans are increasingly turning to what was once a lender of last resort – their 401(k) plans, The Wall Street Journal reported.

In 2010, about one in seven workers borrowed from a 401(k) plan, according to data from human resources consulting group AON Hewitt. Companies that run the plans report double-digit increases in borrowing from 2009, including a 14 percent increase among Vanguard Group Inc.-run plans and an 11 percent increase at plans run by T. Rowe Price Group Inc.

Today, almost 30 percent of 401(k) savers have a loan outstanding, the highest level in recent history.

Last month, Sens. Herb Kohl, a Wisconsin Democrat, and Mike Enzi, a Wyoming Republican, introduced the Savings Enhancement by Alleviating Leakage in 401(k) Savings Act, which would ban products that promote withdrawals, such as 401(k) debit cards.

“A loan from your 401(k) has the potential to leave deep, deep wounds,” said Thomas Muldowney, a financial adviser with Savant Capital Management in Rockford, Ill.

To see the full story in The Wall Street Journal, click here.