The Air Force has seen "solid progress on reducing smoking pretty significantly among airmen," but is still seeing high usage of smokeless tobacco, the service's top medical official told Air Force Times Tuesday.

Surgeon General of the Air Force Lt. Gen. Dr. Mark Ediger said that troops are still using chewing tobacco products at rates higher than civilians.

"We’ve seen a significant reduction in smoking among airmen over the past two years. That’s been a great thing to see," he said. "What we have not seen is a reduction in the use of smokeless tobacco … and so that’s where we’re focusing a lot of our prevention efforts now, is educating airmen on the hazards of smokeless tobacco."

According to the Centers for Disease Control and Prevention, smokeless tobacco is just as harmful as smoking and can lead to cancer. It can also destroy gums and cause tooth decay and loss of teeth.

In 2015, an estimated 7.4 percent of airmen used smokeless tobacco, according to Col. Dr. John Oh with the Air Force Medical Support Agency.

"If the Air Force was a state, we would have the second lowest smoking prevalence in the nation — that's the good news," Oh said in an official press release. "But we would also have the fourth highest smokeless tobacco use."

The Air Force is also looking at 'electronic cigarettes' that deliver nicotine with flavorings and other chemicals to users in vapor instead of smoke.

"The other piece that's out there that we don't have a good picture on yet is the e-cigarette part," Ediger said. "We're working now to be able to actually measure the utilization of e-cigarettes [in the Air Force]. We know we need to factor that in."

Tobacco usage costs the military roughly $1.6 billion a year in medical expenses and lost work time, according to a 2014 Defense Department memo signed by the undersecretary of defense for personnel and readiness.

The Air Force has put "significant restrictions on where tobacco can be used on our installations," Ediger said.

In late March 2015, the service banned smoking in base recreation areas such as beaches, parks, bowling allies and basketball courts.

But the service hasn't banned tobacco outright.

"As a physician, I'm very concerned about tobacco. It's the number one cause of preventable death in the U.S.," Ediger said. "While I as a physician may love to see a policy like that [banning tobacco use in the Air Force], I know that there really would be significant concern about limiting people's choices. There's always that balancing act between doing what we know is in the best interest of somebody's health and overly restricting their personal choices."