Consumers tend to overestimate the amount of whole grains in food products due to confusing and inconsistent labeling, according to a new study.

Researchers from Tufts University and the NYU School of Global Public Health asked 1,030 adults to evaluate both hypothetical and real labeling for bread, crackers and breakfast cereals containing whole grains. They were asked to evaluate the whole grain content of the real products and choose the healthier option among the hypothetical ones.

For the hypothetical products, incorrect responses ranged from 29% to 37% for crackers, to 47% for bread. For the real ones, 41% overstated the whole grain content for multigrain crackers, 43% for honey wheat bread, and 51% for 12-grain bread.

The researchers say manufacturers are intentionally confusing consumers.

“Manufacturers have many ways to persuade you that a product has whole grain even if it doesnt,” said Tufts professor Parke Wilde. “They can tell you its multigrain or they can color it brown, but those signals do not really indicate the whole grain content.”