Olive oil Orange Almonds Kale Percent of nutritionists saying a food is healthy Spinach Eggs 100% Apple Hummus Quinoa Oatmeal Carrots Avocados Cashews 90% Cottage cheese Turkey Chicken Quinoa, lauded as a "superfood," was rated healthy by about 90 percent of nutritionists. Ordinary Americans were uncertain. Shrimp Whole wheat bread Tofu Canned tuna 80% Sushi Skim milk Peanut butter Corn Wine 70% Whole milk Baked potatoes Popcorn Both nutritionists and the public were split about the healthiness of many common items, including butter, red meat, whole milk and cheddar cheese. Steak Orange juice 60% Pork chops Cheddar cheese Granola 50% Foods along this line were rated equally by nutritionists and the public. Coconut oil 40% Frozen yogurt Butter Hamburgers Kind bar 30% Pizza Beer Crackers No food elicited a greater difference of opinion between experts and the public than granola bars. About 70 percent of Americans called it healthy, but less than 30 percent of nutritionists did. Granola bars 20% Beef jerky Diet soda White bread American cheese SlimFast shake Chocolate chip cookies 10% Bacon Ice cream Percent of all Americans saying a food is healthy French fries Regular soda 20% 30% 40% 50% 60% 70% 80% 90% 100% Olive oil Orange Almonds Kale Percent of nutritionists saying a food is healthy Spinach Eggs 100% Apple Hummus Quinoa Oatmeal Avocados Carrots Cashews 90% Cottage cheese Turkey Chicken Quinoa, lauded as a "superfood," was rated healthy by about 90 percent of nutritionists. Ordinary Americans were uncertain. Shrimp Whole wheat bread Tofu Canned tuna 80% Sushi Skim milk Peanut butter Corn Wine 70% Whole milk Baked potatoes Popcorn Both nutritionists and the public were split about the healthiness of many common items, including butter, red meat, whole milk and cheddar cheese. Steak Orange juice 60% Pork chops Cheddar cheese Granola 50% Foods along this line were rated equally by nutritionists and the public. Coconut oil 40% Frozen yogurt Butter Hamburgers Kind bar 30% Pizza Beer Crackers No food elicited a greater difference of opinion between experts and the public than granola bars. About 70 percent of Americans called it healthy, but less than 30 percent of nutritionists did. Granola bars 20% Beef jerky White bread Diet soda American cheese Slimfast shake Chocolate chip cookies 10% Bacon Ice cream Percent of all Americans saying a food is healthy French fries Regular soda 20% 30% 40% 50% 60% 70% 80% 90% 100% Olive oil Orange Almonds Kale Percent of nutritionists saying a food is healthy Spinach Eggs 100% Apple Hummus Quinoa Oatmeal Avocados Carrots Cashews 90% Cottage cheese Turkey Chicken Quinoa, lauded as a "superfood," was rated healthy by about 90 percent of nutritionists. Ordinary Americans were uncertain. Shrimp Whole wheat bread Tofu Canned tuna 80% Sushi Skim milk Peanut butter Corn Wine 70% Whole milk Baked potatoes Popcorn Both nutritionists and the public were split about the healthiness of many common items, including butter, red meat, whole milk and cheddar cheese. Steak Orange juice 60% Pork chops Cheddar cheese Granola 50% Foods along this line were rated equally by nutritionists and the public. Coconut oil 40% Frozen yogurt Butter Hamburgers Kind bar Pizza 30% Beer Crackers No food elicited a greater difference of opinion between experts and the public than granola bars. About 70 percent of Americans called it healthy, but less than 30 percent of nutritionists did. Granola bars 20% Beef jerky White bread Diet soda American cheese Slimfast shake Chocolate chip cookies 10% Bacon Ice cream Percent of all Americans saying a food is healthy French fries Regular soda 20% 30% 40% 50% 60% 70% 80% 90% 100% Olive oil Orange Almonds Kale Percent of nutritionists saying a food is healthy Spinach Eggs 100% Apple Hummus Quinoa Oatmeal Avocados Carrots Cashews 90% Cottage cheese Turkey Chicken Shrimp Whole wheat bread Tofu Canned tuna 80% Sushi Skim milk Peanut butter Both nutritionists and the public were split about the healthiness of many common items, including butter, red meat, whole milk and cheddar cheese. Corn Wine 70% Whole milk Baked potatoes Popcorn Steak Orange juice 60% Pork chops Cheddar cheese Granola 50% Foods along this line were rated equally by nutritionists and the public. Coconut oil 40% Frozen yogurt Butter Hamburgers Kind bar 30% Pizza Beer Crackers Granola bars 20% Beef jerky White bread Diet soda American cheese Slimfast shake Chocolate chip cookies 10% Bacon Percent of all Americans saying a food is healthy Ice cream French fries Regular soda 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Pinch to zoom

Is popcorn good for you? What about pizza, orange juice or sushi? Or frozen yogurt, pork chops or quinoa?

Which foods are healthy? In principle, it’s a simple enough question, and a person who wishes to eat more healthily should reasonably expect to know which foods to choose at the supermarket and which to avoid.

Unfortunately, the answer is anything but simple.

The Food and Drug Administration recently agreed to review its standards for what foods can be called “healthy,” a move that highlights how much of our nutritional knowledge has changed in recent years – and how much remains unknown.

With the Morning Consult, a media and polling firm, we surveyed hundreds of nutritionists – members of the American Society for Nutrition – asking them whether they thought certain food items (about 50) were healthy. The Morning Consult also surveyed a representative sample of the American electorate, asking the same thing.

The results suggest a surprising diversity of opinion, even among experts. Yes, some foods, like kale, apples and oatmeal, are considered “healthy” by nearly everyone. And some, like soda, french fries and chocolate chip cookies, are not. But in between, some foods appear to benefit from a positive public perception, while others befuddle the public and experts alike. (We’re looking at you, butter.)

“Twenty years ago, I think we knew about 10 percent of what we need to know” about nutrition, said Dariush Mozaffarian, the dean of the Tufts Friedman School of Nutrition Science and Policy. “And now we know about 40 or 50 percent.”

Here’s what we found.

Foods considered healthier by the public than by experts Percent describing a food as “healthy” Nutritionists Public Difference

Of the 52 common foods that we asked experts and the public to rate, none had a wider gap than granola bars. More than 70 percent of ordinary Americans we surveyed described it as healthy, but less than a third of nutritional experts did. A similar gap existed for granola, which less than half of nutritionists we surveyed described as healthy.

Several of the foods considered more healthful by everyday Americans than by experts, including frozen yogurt, a SlimFast shake and granola bars, have something in common: They can contain a lot of added sugar. In May, the Food and Drug Administration announced a new template for nutrition labels, and one priority was to clearly distinguish between sugars that naturally occur in food and sugars that are added later to heighten flavors. (You’d be surprised how many foods contain added sugar.) It’s possible nutritionists know this, but the public still does not.

Foods considered healthier by experts than by the public Percent describing a food as “healthy” Nutritionists Public Difference

On the other end of the spectrum, several foods received a seal of approval from our expert panel but left nonexperts uncertain. Most surprising to us was the reaction to quinoa, a “superfood” grain so often praised as healthful that it has become the subject of satire. (At the moment, The New York Times cooking site offers 167 recipes for quinoa, roughly a third of which are explicitly tagged “healthy.”)

In addition, tofu, sushi, hummus, wine and shrimp were all rated as significantly more healthful by nutritionists than by the public. Why?

One reason may be that many of them are new foods in the mainstream American diet. Our colleague Neil Irwin measured mentions of trendy foods in Times coverage over the years, and found that quinoa had only recently picked up steam. Others may reflect mixed messages in press coverage of the healthfulness of foods. Shrimp was long maligned for its high rate of dietary cholesterol, though recent guidelines have changed. And public messages about the healthfulness of alcohol are conflicting: While moderate drinking appears to have some health benefits, more consumption can obviously have real health costs.

We weren’t surprised to find areas in which both ordinary Americans and experts disagreed.

We expect researchers to be better informed about current research, and everyday consumers to be more susceptible to the health claims of food marketers, even if the claims are somewhat dubious.

But some of the foods in our survey split both the public and our panel of experts.

Foods that both experts and the public have mixed feelings about Percent describing a food as “healthy” Nutritionists Public Difference

Four of the foods listed above – steak, cheddar cheese, whole milk and pork chops – tend to have a lot of fat. And fat is a topic few experts can agree on. Years ago, the nutritional consensus was that fat, and particularly the saturated fat found in dairy and red meat, was bad for your heart. Newer studies are less clear, and many of the fights among nutritionists tend to be about the right amount of protein and fat in a healthy diet.

The uncertainty about these foods, as expressed both by experts and ordinary Americans, reflects the haziness of the nutritional evidence about them. (If you’re a steak lover and you find this news discouraging, our colleague Aaron Carroll has written that red meat is probably fine in moderation.)

It’s clear that many shoppers do want to eat healthful foods but are unsure what to choose. To gain some perspective on this, we asked Google which foods were most commonly part of a simple search: “Is [blank] healthy?” We used these results to generate some of our survey questions. The food people were likeliest to ask about was also one nutritionists generally approve of: sushi.

Is _________ healthy? What American internet users searched for most often

There are some areas of nutritional consensus. Nearly everyone agreed that oranges, apples, oatmeal and chicken could safely be described as healthy, and also agreed that chocolate chip cookies, bacon, white bread and soda could not.

Foods that both groups think are unhealthy Percent describing a food as “healthy” Nutritionists Public Difference

Foods that both groups think are healthy Percent describing a food as “healthy” Nutritionists Public Difference

Where does this leave a well-meaning but occasionally confused shopper? Reassured, perhaps: Nutrition science is sometimes murky even to experts.

Your overall diet probably matters a lot more than whether you follow rigid rules or eat just one “good” or “bad” food. Our colleague Aaron Carroll has published a list of common-sense rules for healthful eating, which represents a good start.