Public Health Policy - Shaped by science, opinion, or politized?

Over the past century, rigorous safety and ethical standards have been developed in order to prevent patient harm in research with humans and animals. In fact all institutions doing research with humans or animals need to have an Institutional Review Board (IRB) in order to conduct research. A perspective in today's New York Times suggest that NYC may attempt to be their "own" IRB, which adds to many articles written about this directive over the past several months.

NYC has been trying to make several community level changes in order to improve the health of its city. Many of the mandates have been very controversial. One instance was the requirement that all restaurants need to have the nutritional value posted for their food items. The indoor clean air quality act was one in order to prevent exposure to second hand smoke. Another example is the trans fats ban.

The risk in the most recent idea to require restaurants to cut the sodium levels in half. Mr. Tierney points out is that there is very controversial evidence that this is an effective strategy to prescribe a widespread mandate for lower sodium in NYC. Moreover, the fact that there has been controversy within the medical community is worrisome since its the basis of this public policy initiative.

It's very alarming that this could be rolled out across a city without large agreement within the scientific community. Normally, as the article mentions, this would have to be exposed to the rigor of scientific safety standards to protect the individual. On a community level, this would mitigate the normal well intended safety standards.

I think we can all agree that science and policy must become more united in order to reduce the incidence of obesity, type II diabetes, and cardiovascular disease in the United States. However, I'm not sure that this is the best way to approach it. Creating increased access to mass transit, constructing additional bike lanes, constructing running lanes in parks, encouraging citizens to walk and excersize, removing soda and vending machines from schools,  etc, all seem like better, longer-lasting solutions. 

It's tricky to get an overweight country to become more active and to make better decisions about what to eat and to become more active. On the other hand, doing nothing isn't trimming down the epidemic, its expanding just like the waistlines of Americans. What do you think about this reform strategy?