New York City, in its unending love for its citizens is considering a ban on trans fats in all restaurants. The AP reports: 
Three years after the city banned smoking in restaurants, health
officials are talking about prohibiting something they say is almost as
bad: artificial trans fatty acids.
The city health department unveiled a proposal Tuesday that would
bar cooks at any of the city’s 24,600 food service establishments from
using ingredients that contain the artery-clogging substance, commonly
listed on food labels as partially hydrogenated oil.
Artificial trans fats are found in some shortenings, margarine and
frying oils and turn up in foods from pie crusts to french fries to
At the bottom of the story comes a reaction from academia:
Dr. Walter Willett, chairman of the Department of Nutrition at the
Harvard University School of Public Health, praised New York health
officials for considering a ban, which he said could save lives.
"Artificial trans fats are very toxic, and they almost surely
causes tens of thousands of premature deaths each year," he said. "The
federal government should have done this long ago."
Almost surely. They almost surely cause tens of thousands of premature deaths. Probably. Maybe. But it’s OK. It’s a move toward health and who can be against that?
Wake up out there, folks. This is the death of liberty by a thousand cuts. And how do you argue against any one of those sword thrusts? It seems pretty silly to take a stand in favor of trans fats. They’re clearly not good for you. I doubt they cause tens of thousands of premature deaths but they’re probably not the best thing to put in your body. So how do you fight this? Is it really such a big deal if one ordinance gets passed that’s well-motivated and enacted to save lives?
Actually, I think it’s a very big deal. And I encourage you to hear what Ed Glaeser has to say  about government paternalism. I think he comes up with some very powerful arguments for why this kind of "public health" measure is dangerous rather than benign.
One argument he makes is the slippery slope argument. First the government puts a warning label on cigarettes on the grounds that it’s not really an infringement of liberty—after all, you’re still free to smoke. This is followed by real regulation. Bans on smoking in public. Enormous taxes and bans on entry.
The trans fat think is going the same way. It starts out with mandatory labeling. Who can be against that? Then an outright ban is proposed. Well come on, we know it’s dangerous don’t we?
First of all, dangerous is a meaningless term. It makes for good politics but lousy economics and takes the joy of life. Everything is dangerous. Skiing is dangerous. Bicycles are dangerous. Swimming pools are dangerous. Even Vitamin C is dangerous.
One reason we don’t want the government banning "dangerous" products is because it’s undefinable. Another reason is because the government doesn’t always know the real risk of something.
But the most important reason we don’t want the government banning "dangerous products is that the government doesn’t love me. It doesn’t care about me. Walter Willet of Harvard doesn’t love me. From the same AP article, here’s the bureaucrat pushing this idea:
Health Commissioner Thomas Frieden acknowledged that the ban would
be a challenge for restaurants, but he said trans fats can easily be
replaced with substitute oils that taste the same or better and are far
"It is a dangerous and unnecessary ingredient," Frieden said. "No one will miss it when it’s gone."
Thomas Frieden doesn’t love me either. Doesn’t care about me. Doesn’t know me. Doesn’t know my relative likes and dislikes. Doesn’t know how trans fats affect me or give me pleasure or cause me pain. Doesn’t know my tolerance for risk.
But it’s worse than that. It’s not just that Thomas Frieden wants to do good but has imperfect information. He doesn’t only want to do good. His real full set of motivations is more complex. There are political pressures on him. Which brings me to the quiet side of this story. Why trans fat? Why now? What else is going on? Is there some group out there that has a stake in the trans fat ban that is hidden? What products would be used in place of trans fat? Do the makers of those products have a stake in quietly lobbying the city of New York to enrich them in the name of public health?
And once you’re in that world, and that is the real world that Thomas Frieden lives in, why would you ever assume that the Thomas Frieden’s of the world have the incentive to do the right thing?
If you live in New York, and even if you don’t, speak out against this proposed ban. If you don’t live there, speak out, too.
The Mayor’s office invites feedback.  Email the mayor, Michael Bloomberg. Email Thomas Frieden. Politely let them know that you would like to make your own choices about what you eat. Tell them that if trans fat is so obviously bad for you, you’d expect restaurants to eliminate them on their own and to start advertising that they are trans fat free. Tell them that you expect the government to stay out of the kitchen and the bedroom and the ski slope and everywhere else that we make choices that are best left to ourselves and out of the hands of power where those decisions can be influenced by special interests. And tell them that the road to hell is paved with good intentions.