LONDON — Whole grains stood out among dietary staples as a food that is positive for digestive health, according to a survey from the London-based consultancy New Nutrition Business. Among consumers asked whether various food choices are good or bad for digestive health, 61% said whole grains are good, and only 4.5% said whole grains are bad.

The survey involved 3,000 people from the United Kingdom, Australia, Spain, Brazil and the United States. At 4.5%, whole grains had the fewest naysayers of any of the 11 categories included in the survey. Only fruit, vegetables and yogurt had higher “good for digestive health” scores, at 83%, 78% and 69%, respectively.

The whole grains “good for digestive health” figure of 61% easily topped 47% for dairy milk and 28% for meat.

Overall, grain-based foods received mixed reviews in the survey. Bread was described as good for digestive health by 24% of respondents but bad by 39%. By contrast, breakfast cereals were described as good by 36% and bad by 12%.

The Grain Foods Foundation, Washington, has pointed to bread’s fiber content as a positive in digestive health. In Americans’ diets, grains provide 23% of the fiber, which adds bulk to the diet, helps with digestion and helps prevent constipation. White bread contains 2 grams of fiber per 100 grams, and whole wheat bread contains 6.5 grams of fiber per 100 grams.

As was the case for bread, consumers were highly conflicted about many foods, with a large percentage of respondents describing the product as good for digestive health and many remaining respondents describing the food as bad. For instance, 28% of consumers believe meat is good for digestive health, and 33% believe it is bad. While 47% of consumers believe dairy milk is good for digestive health, 31% believe it is bad.

“Contradictory consumer beliefs about which foods are good or bad for digestive health indicate how strongly attitudes about food and health are fragmented,” said Joana Maricato, research manager at New Nutrition Business. “Most people are adopting a wide variety of behaviors in relation to diet and health.”

She gave mistrust in official dietary guidelines as a reason for the variety of behaviors. In the survey 76% said they thought messages about diet and health were confusing.

“Changes in dietary advice over the past 15 years have created consumer skepticism about the expert opinions of dietitians and nutrition researchers, just at the moment that technology has made it easier for people to find dietary information for themselves,” Ms. Maricato said.

Specialty products touted for their beneficial gut health properties did not fare well in the study. Only 18% of respondents said kefir is good for digestive health, and 16% said sauerkraut/fermented vegetables are good for digestive health.

More than half of the survey respondents (54%) said they searched online and read blogs when they wanted to know more about healthy eating and diet.