Earlier this month, spurred by a group of local students, the South Portland City Council banned the use of tobacco products from city-owned parks, beaches and recreation facilities.

Around the same time the South Portland council was debating the merits of the smoking ban, officials at the Los Angeles Unified School District were eliminating flavored milk from school menus, at the behest of a celebrity TV chef and child obesity advocate.

While chocolate milk and cigarettes may not seem to have a lot in common, they are in this case both signs of how it is becoming increasingly acceptable for government to impose on residents its idea of healthy living. It is a trend that bears watching, as officials walk the line between good public health policy and infringing on personal freedom.

It is a line that has never seemed so blurry, because what start as government actions with the best of intentions open the way for the slow eroding of personal freedoms. Officials get incrementally more comfortable with taking things away, and the public gets incrementally more comfortable with having them taken.

Take the ban on smoking, for example. First, smoking bans were enacted in workplaces, then restaurants, then bars, all of which were first met with resistance before becoming commonplace. But now, South Portland’s ban extends to all city-owned properties, including vast outdoor parks. In addition, a 25-foot no-smoking buffer zone extends from the property line out 25 feet, unless the neighboring land is a private residence. That means a business that borders city property cannot have a smoking area with 25 feet of the line, even on its own property.

Also, the ban applies to all tobacco products, not just cigarettes, so chewing tobacco is gone, as well, all because of an ordinance originally intended to keep people from blowing smoke on their fellow beachgoers.

And South Portland is far from alone. In April, Scarborough enacted a similar smoking ban, and Westbrook, Portland and Lewiston already had tobacco bans on the books. University of Maine established a voluntary no-smoking policy on campus for 2011, and a mandatory ban goes into effect Jan. 1. Smoking has been banned for two years now at all state parks.

Now, few can argue with the health benefits that have been gained as restrictions on smoking have tightened. It is certainly much more enjoyable to go into a bar or a restaurant without having to squint through a thick wall of cigarette smoke, and fewer places to smoke means fewer people will start and keep smoking.

But the same argument used to ban smoking – that it is unhealthy for both the smokers and those nearby – can, and has, been used to forward other public health causes, such as the chocolate milk ban.

And that is where the ground really becomes shaky.

Ben Bragdon is the managing editor of Current Publishing. He can be reached at bbragdon@keepmecurrent.com or followed on Twitter.