Advisers to the Food and Drug Administration voted 14-2 on Wednesday to recommend that all new diabetes drugs undergo longer studies to assure they don't increase risks of heart problems. The agency currently doesn't screen for heart risks associated with diabetes drugs.

The opinions from diabetes experts, cardiologists and statisticians come less than a year after the FDA was criticized for its handling of heart risks connected with a widely used GlaxoSmithKline pill. The drug was approved in 1999, but the agency didn't add a warning about potential heart risks until last November.

The majority of the panel said drug companies could begin safety testing before they submit drugs to the FDA and finish the studies after the drugs are on the market. The testing would take an estimated five years to seven years to complete, and likely cost tens of millions of dollars.

At least one panelist doubted whether the proposed studies would actually uncover heart risks, and added they could delay important medical breakthroughs.

"If you wait this amount of time for testing you're going to be preventing certain drugs from getting out there that may be better than what we already have," said Dr. Eric Felner, a pediatric specialist at Emory University School of Medicine.

The FDA is not required to follow the panel's advice, though it often does.

GlaxoSmithKline PLC, AstraZeneca and Novartis AG are among the companies developing diabetes treatments to compete in the domestic market, which grew to more than $6 billion last year, according to pharmaceutical research firm IMS Heath.

Takeda Pharmaceuticals' Actos, GlaxoSmithKline's Avandia, and Eli Lilly and Amylin Pharmaceutical's Byetta currently dominate the U.S. market.

Nearly 24 million Americans have Type 2 diabetes, which can lead to kidney failure, blindness and heart disease.