Social engineering is a tool of an overbearing state, rarely works, and seeks to render undue control and influence over social liberties. In sum, it is a poor mechanism for influencing behavior.
If we want to encourage a healthier populace we must provide the incentive for such; this would include the penalties associated with poor choices. The current health insurance model allows for -- possibly enables and even encourages -- irresponsible behaviors. In fact, its very construct is escalatory in nature. The consumer has two levels of "shielding" from their real-time consumption; the first is the delay of cost realization in the annualized nature of premiums and the second being the disseminated risk amongst their risk pool cohorts. This shielding results in a cost oblivious consumer, diminished penalties for consumption, etc.
We must make the consumer aware of the economic burdens associated with their lifestyle and treatment decisions. In order to do this we must necessarily move away from the entitlement mentality that has been brought about through federal intervention (remember, the employer sponsored health insurance model is the direct result of ill conceived and ill fated government interventions in the form of wage and price controls). We need to return "health status ownership" back to the individual in some fashion. Failure to do so will not address the core issue... and will ultimately fail.