NEW YORK — A shift in how consumers perceive food and beverage products may be under way, according to a study conducted by the Food Marketing Institute and Prevention magazine. What used to matter most to consumers was which undesirable characteristics their foods did not contain, such as fat, sugar, salt, calories, etc. Now the demand for products featuring ingredients perceived as healthy is on the rise, with fiber being the most sought-after ingredient followed by whole grains, protein, omega-3 fatty acids and antioxidants.

“While the main criteria for healthy foods was previously determined by ingredients it did not contain, today’s shoppers are now instead wondering what’s in their food, seeking to better understand the nutritional components of what they eat,” said Cary Silvers, director of consumer insights for Prevention.

Despite the focus on positive ingredients, the survey, titled “Shopping for health,” also showed that a lack of planning is trumping health in the decision-making process at the American dinner table with 72% of consumers deciding what to have for dinner that day. When same day decisions for dinner are made, health falls well behind taste, convenience and craving. The lack of meal planning is so pervasive that almost one-in-four shoppers decide what to have for dinner within one hour before eating.

“Helping food retailers provide their customers with the information they need to make nutritious choices and develop healthy eating habits remains a clarion call for F.M.I.,” said Leslie G. Sarasin, president and chief executive officer for the association. “As schedules become busier and awareness of health issues increase, the consumer demand for healthful options that are quick and easy for families will grow.”

A majority of consumers read food labels, but the survey showed that the number of consumers who read food labels has declined to 64% in 2010 after totaled 71% in 2007 and 2008, and 67% in 2009. Those consumers who are reading food labels said they are buying products with certain types of ingredients. More than half said they have been buying more whole grain products in the past year. The numbers are also up for low sodium, natural, low fat and low-, zero-calorie.

The data for the “Shopping for health” survey were collected by Harris Interactive through an online survey between Nov. 19, 2010, and Dec. 1, 2010, and included 1,579 U.S. consumers.