There is an epidemic of gun violence. This is a serious health problem. Watching your diet, exercising, and taking pills is all for naught if a bullet kills you.

In Newtown, Conn., one of the worst mass shooting occurred last week when a gunman shot his mother at home, apparently with her own gun, then walked into an elementary school and shot six other adults and 20 children, before shooting himself. Gun rights are hotly debated and highly politicized, but gun violence is a serious health issue. The National Rifle Association (NRA) and others have been strong proponents of gun rights, and have fought hard to fight off attempts for even the slightest form of control, including restrictions on semi-automatic and assault weapons.

One of their arguments is that citizens can protect themselves with guns, and that concealed guns are a particularly effective deterrent because potential assailants won’t know who may be armed. But in 61 cases in the U.S. in the past 30 years, maybe only one was stopped by a gun other than their own, or by the police. Even if people want guns to protect themselves, they shouldn’t need to cover the contingency of an invading army, so I see no need for high capacity bullet magazines.

Many mass shooters have mental illness and we need to do a better job providing access to mental health treatments. Some illnesses, such as schizophrenia, often don’t really manifest until people are in their teens or early 20s, allowing them to purchase guns when their sick enough to do real damage, but not so severe that they would have more trouble planning an attack or convincing someone to sell them a gun.

Even if not mentally ill, young men tend to act less rashly as they get older, and are more likely to consider the consequences of their actions. From a list of 22 of the deadliest mass shootings around the world, 65% of them were under 30. We already have a law that says that people can’t buy alcohol until they are 21-years-old, even though they can vote and serve in the military at 18years old. Perhaps the right to own a gun should only be allowed for those who are at least 30 years old.

We need to close legal loopholes, such as sales between private buyers, that allow people to avoid background checks before purchasing guns. I need to fill out more paperwork to prescribe shoes for a diabetic than to buy an assault weapon. We need people to speak up and let our politicians know that gun violence caused by guns is not acceptable. We’ll never prevent all such tragedies, but we should try to minimize the possibility as best we can.

Daniel Ginsberg is an internal medicine physician who blogs at World’s Best Site.