The use of flavors in different tobacco products has the potential to do "both harm and good,” the Food and Drug Administration’s chief said Thursday, explaining that the agency would weigh both possibilities as it considers banning flavors such as menthol in cigarettes and e-cigarettes.

The FDA’s review of flavors is part of a sweeping overhaul of tobacco regulation in which the agency hopes to mandate a reduction of nicotine in cigarettes to such a low level that they are no longer addictive, and at the same time encourage smokers to switch to less-harmful products such as e-cigarettes.

The FDA concluded in 2013 that menthol cigarettes were harder to quit and likely posed a greater health risk than regular cigarettes. The agency since then has been considering regulatory action to restrict menthol sales but has remained quiet on the issue for the past few years. The tobacco industry has rejected the FDA’s findings.

“On this issue, we see two sides—on the one hand, we need to know the role that flavors, including menthol, play in attracting youth to initiate tobacco use,” FDA Commissioner Scott Gottlieb said Thursday in a speech at Johns Hopkins Bloomberg School of Public Health. “But on the other hand, we also need to know whether…certain flavors may help adult cigarette smokers switch to potentially less harmful forms of nicotine delivery” such as e-cigarettes.

The agency will issue regulations based on flavors’ “net impact to public health,” he said.