Vin Suprynowicz

City health departments do some useful work, on balance.

They were mostly born of the “sanitary” and “hygienic” movements of the late 19th and 20th centuries. Appalled by the squalor and disease in the nation’s crowded tenements, volunteers — at first — set about informing people about how diseases were transmitted, stressing the importance of sanitation, clean water, removing the garbage that drew rats and other vermin.

They accomplished great good. Today, however, it’s rarely considered enough to merely “inform” the public, nor are the forces of “public health” mere private volunteers whose advice we may decide whether or not to heed.

Now they’re backed by the force of law.

Take New York’s health department, and its activist standard bearer, millionaire Mayor Michael Bloomberg.

So far, neither the citizens nor the courts of the Big Apple have seen fit to rein in Mayor Bloomberg’s campaigns to ban public smoking and the use of “trans fats” in city restaurants. So, the mayor has decided to keep going in his efforts to save us from ourselves.

The latest target? Salt.

On Monday, the Bloomberg administration unveiled a broad new health initiative aimed at “encouraging” food manufacturers and restaurant chains across the country to curtail the amount of salt in their products.

The plan, for which the city claims support from health agencies in other cities and states, sets a goal of reducing the amount of salt in packaged and restaurant food by 25 percent over the next five years.

Public health experts say that would reduce the incidence of high blood pressure and should help prevent some of the strokes and heart attacks associated with that condition.

“We all consume way too much salt, and most of the salt we consume is in the food when we buy it,” said Dr. Thomas Farley, the city’s health commissioner, whose department is leading the effort. Eighty percent of the salt in Americans’ diets comes from packaged or restaurant food, Dr. Farley says.

Needless to say, the New Yorkers insist corporate cooperation with the scheme will be entirely “voluntary.”

Those who were once asked to “voluntarily” wear seat belts and motorcycle helmets, immunize their children, and limit their smoking in public places — not to mention those who keep asking just how low MADD would like to drive the permissible “blood alcohol content” for drivers — may be excused if they take their pencils and add to the end of such a sentence: “… for now.”

It would indeed be healthier if most Americans ate less salt. But two things should be noted.

First, if the “save us from ourselves” movement goes too far, and eventually triggers a pendulum swing in the other direction, mobs fed up with being told what to do may not stop till they’ve also rebelled against and repealed much of the legitimate good the public health movement has achieved.

And second, we should not allow the descendants of the “sanitary” and “hygiene” movements of a century ago to write the histories of their own movements without noting that they have been wrong before.

Many among their number, a century ago, favored forced — or at least, far from fully informed — sterilization of the mentally disabled and of “undesirable” minorities. They also launched, about a century ago, what we now know as the “War on Drugs “ — though of course they swore up and down that they sought only “truth-in-labeling laws,” that no one would EVER interfere with the right of a doctor to prescribe any analgesic he wished, or of adults to buy any drug they desired.

Remind us how that one’s working out — and how America’s incarceration rate now ranks in the world — before you pass the salt.