Today, we have new scares, like the one over plastic water bottles. Some contain a chemical called BPA, which activists say causes cancer, hyperactivity, all sorts of problems.
Chemicals called phthalates, which keep school supplies like backpacks soft, are accused of damaging kids' livers and kidneys and causing asthma.
If these stories were true, who could blame parents for being frightened? Who can blame reporters for telling the story?
Julie Gunlock, from the Independent Women's Forum, blames them. She points out that the activists scare mothers needlessly, because "over 1,000 studies, independent studies, have said that BPA is perfectly safe."
She knows how the scare stories work: "BPA is easily vilified. I mean, it's invisible. And people tend to say: 'Chemicals, it's scary. I'll just trust what some activist organization or consumer rights organization says and avoid it.'"
There's no reason to get excited about chemicals -- unless you're an environmental activist eager to acquire money and power.
"A lot of them make money on newsletters," says Gunlock. "Bad news sells." NRDC has raised $185 million by scaring people.
To keep scares in perspective, remember all the good news that gets less attention. Coverage of horrors like the shooting in Newtown, Conn., makes us think our kids are in more danger today, but school violence is actually down.
And despite all the chemicals -- actually, because of them -- we live longer than ever.
There is plenty of bad news that's real -- like the national debt, and most of what politicians do. But in most ways, most of the time, the world slowly but surely gets better. To most of us, that's good news.