The poll comes on the heels of New York City Mayor Michael Bloomberg's decision to ban the sale of sodas larger than 16 ounces, an initiative that's garnered a lot of media attention and spurred criticism from various groups who argue the government is going too far.

Some public health advocates have argued that taxing junk food will help curb the nation's obesity epidemic. But it's an assumption that consumers don't share: According to the poll, 51 percent disagreed that sales taxes on candies and sodas would help to reduce obesity. Only 26 percent agreed.

Two-thirds say it shouldn't be the role of government to influence what Americans eat and drink to make healthier choices.

Similarly, a study last month from the Harvard School of Public Health found that though the public is very supportive of government action aimed at changing lifestyle choices that can lead to obesity, diabetes and other noncommunicable diseases, they are less likely to support such interventions if they're viewed as intrusive or coercive.

For example, that study found that support was high for interventions that facilitate healthy choices, such as increasing the affordability of fruits and vegetables, requiring more instruction in public schools about the health risks of obesity, and requiring restaurants to post the calorie counts for food they serve.

But support waned when government actions were viewed as focusing on penalties or on limiting choices.