In a 2012 survey of 1,057 adult consumers, the International Food Information Council found that 91% of the respondents perceived themselves to be in excellent, very good or good health. The finding corresponds to a survey conducted by the Centers for Disease Control and Prevention in 2010 in which 88% of 27,157 respondents said they are in at least good health.

The results of these two surveys highlight the challenges public health officials and private sector executives are facing when they try to develop products, programs and partnerships to help consumers improve their diet and focus on being healthier.

When asked by IFIC to rate their diets, 77% of respondents said their diet was extremely healthy, very healthy or somewhat healthy. Yet in apparent contrast with their self perception, 55% said they are trying to lose weight.

Given the current rate of obesity in the United States and the alarming rise in the diagnosis of type 2 diabetes among adults and children, it is clear there is a disconnection between what consumers perceive to be healthy and what is actually healthy. This disconnection is at the heart of why many of the obesity-related public health initiatives may not be effective.

Calorie counts on menus, proposed junk food taxes, carbonated soft drink bans or the mandating that only certain portion sizes may be sold in specific food service venues are not likely to be effective. How can a program or initiative succeed if the intended audience doesn’t understand the program is targeted at them?

Much has been written about the rise of obesity in developed economies and the need to educate consumers to be more proactive about improving their health through diet and exercise. But a key finding from IFIC’s survey highlighted at least one impediment to consumers being more proactive — a majority of respondents said it is easier to do their own taxes than to improve their diet and health.

Even more disturbing is fewer than one in 10 respondents to IFIC’s survey correctly estimate the number of calories they need to consume to maintain their weight, and only 3 in 10 believe that all sources of calories play an equal role in weight gain. Calories from sugar, carbohydrates and fats are believed more likely to cause weight gain.

To the average consumer, diet and nutrition are complex subjects. The issue is made more problematic because as an individual ages and goes through the different stages of life their nutritional needs change.

There are numerous facets to the relationship between diet, exercise and overall health, and many are beyond the reach of the food and beverage industry. Yet when the subject of obesity is broached, food manufacturers are subjected to a significant amounts of blame.

This challenge was made abundantly clear this past month when New York Mayor Michael Bloomberg and the city’s public health department proposed banning specific sizes of sugary beverages from being sold in certain types of venues such as movie theaters. Despite featuring product portfolios with many healthy options, the leading beverage companies, The Coca-Cola Co. and PepsiCo, Inc., found themselves being criticized.

Rather than rely on gimmicks such as New York’s proposed large-size beverage ban, it may be more proactive to address what consumers know about nutrition. Many programs already are in place with that goal, most notably the U.S. Department of Agriculture’s MyPlate graphic.

Conventional wisdom holds that con-sumers know what they need to do to eat right and maintain a healthy weight. But what if the conventional wisdom is wrong? Information from surveys conducted by IFIC and the C.D.C. have repeatedly shown that the heart of the issue may not be a lack of willpower but a lack of knowledge.