Four in five US consumers are more concerned about health, nutrition, and fitness than they were a year ago, according to a survey.

The study, carried out by food industry analyst Phil Lempert, surveyed around 3,000 consumers. Those asked also revealed that nutrition had replaced fitness as the prime consumer concern.

"Shoppers care more than ever about the kinds of foods they buy and a growing number of consumers especially want to know where their foods came from and how they were raised or grown," Lempert said.

The survey, which evaluated consumers' attitudes toward selecting foods, showed that 95% of consumers were concerned about nutrition, which Lempert said explains why there is a growing interest in fresh fruit and vegetables.

The survey also revealed that some 84% of consumers polled were aware that the actual nutrient value of fresh produce could vary, according to production practices. And some 55% said they thought organic foods contained the best nutrient levels.