HLOL Podcast Transcripts

Health Literacy

Encouraging Healthy Food Choices with Traffic-Light Labels and Choice Architecture (HLOL #195)

Helen Osborne: Welcome to Health Literacy Out Loud. I’m Helen Osborne, President of Health Literacy Consulting, founder of Health Literacy Month and author of the book Health Literacy from A to Z: Practical Ways to Communicate Your Health Message. I also produce and host this podcast series, Health Literacy Out Loud.

Today, I’m talking with Dr. Anne Thorndike, who is an Associate Professor of Medicine at Harvard Medical School and an internist at Boston’s Massachusetts General Hospital, otherwise known as MGH.

Much of Dr. Thorndike’s work focuses on individual and population-level behavioral interventions to prevent cardiometabolic disease.

Through implementation research, she and her team demonstrated the effectiveness of traffic light labels, choice architecture, social norms and financial incentives to promote healthy food choices in real-life settings, such as workplace cafeterias and supermarkets.

I learned of this work when I was reading a paper in JAMA Network Open. The article was called “Calories Purchased by Hospital Employees After Implementation of a Cafeteria Traffic Light-Labeling and Choice Architecture Program.” It was written by Dr. Thorndike and some of her colleagues.

I was so impressed by this that I invited her to be a guest on Health Literacy Out Loud. Happily, she said yes. Welcome.

Dr. Anne Thorndike: Hi, Helen.

Helen Osborne: I’m so glad you’re with us today. What intrigued me so much about your study was that it seems so doable. I’m not making light of it, but traffic light labeling and moving foods around, you used visual and spatial cues to encourage healthy food choices. Please tell us all more about what you did and why.

Dr. Anne Thorndike: We did this project in our hospital cafeteria. We started in the main cafeteria.

We actually first implemented it about 10 years ago, and at the time, I was working with human resources on an employee wellness project. I think, in general, we all believed that we needed more guidance for people when they were purchasing food at the cafeteria.

In a hospital, as like many workplaces, people buy a lot of their food and meals at work. So this was a good opportunity to help people make healthier choices throughout the year.

It also helps patients and families and provides a good role model in the community for them when they come here to get care.

Helen Osborne: I’ve certainly worked in hospitals, and I’m familiar with MGH. For the listeners who may not be as familiar, it is a very large institution. You have many people coming through all the time, both working there and visitors, correct?

Dr. Anne Thorndike: Correct. I think now we have over 26,000 employees.

Helen Osborne: Oh my goodness.

Dr. Anne Thorndike: And many more patients.

Helen Osborne: Tell us what you did about the food. I agree with you totally that a hospital should be a place that has healthy food. But I certainly remember in my day working at other places there were plenty of cookies all over the place.

What is it you were trying to do? And what is it you did about encouraging healthy food choices?

Dr. Anne Thorndike: What we were not doing was changing out all of the food to make everything absolutely the healthiest choice you could ever make.

Overall, I would say our cafeteria, even 10 years ago, had a good proportion of healthy choices, but there were cookies, French fries and different types of unhealthy choices.

At the time, we decided that the best strategy would be to create this system that would help guide people when they were in the moment of making the choice.

The two aspects of this were labeling the foods either red, yellow, or green, which are pretty self-explanatory. Green meant that it was the healthiest choice, yellow less healthy and for red, our messaging was, “There’s a better choice in yellow or green.”

Helen Osborne: That’s equivalent to a traffic light.

Dr. Anne Thorndike: Exactly, the same type of messaging. Green means go, yellow means slow down, and red means stop, or at least stop and think about it.

Then the other aspect of it was this choice architecture. I learned about this from a colleague or co-investigator who introduced me to behavioral economics, where people are more likely to choose things that are easy for them to see or that are in convenient locations.

You tend to pick the first thing you see rather than trying to hunt around for something.

Helen Osborne: Does that apply just physically? Or is that on the web, too? That you would just do the easiest, quickest thing first.

Dr. Anne Thorndike: We were just doing it physically. You could do it on the web. There are types of people who have tested using menus or changing the location where products are located on a menu, like putting it at the top of the menu or on the first page and that type of thing.

Helen Osborne: Your study was looking at all that you did. Tell us about that. How did you really investigate whether this system works?

Dr. Anne Thorndike: We’ve done a lot of studies, actually. The most recent study we did, did go back to the time where we originally implemented the program.

When we first implemented the program, we up-front decided that we were going to study it. If we were going to do this program, we really should evaluate whether it’s going to actually help people make healthier choices. If it’s not, then it’s really not worth the time and effort to maintain this whole program.

Before we even put the labels on anything or changed the arrangement of foods in the cafeteria, we collected data for three months. We just observed what people did before traffic light labels were there.

We measured the sales of all the different items. We had already identified what was going to be red, yellow, and green, so we already knew that. But people who were buying things couldn’t see that.

For three months, we just saw what people were purchasing with no labels and no choice architecture.

Then after those three months, we had three months where we just had traffic labels in place and no choice architecture. Then after the next three months, we added the choice architecture. Then we followed sales for the next two years.

The paper that we recently published was evaluating the calories purchased by employees during this three-month baseline period and then the following two years to see if there were any changes.

We had already done prior research that had shown that, during this period, people purchased fewer red-labeled items and more green-labeled items. We already knew that it worked from that perspective.

But sometimes, red and green items don’t make sense to people, so we really wanted to demonstrate that we actually were making a change in the total number of calories that people were purchasing.

What we found was that during the two years, people reduced their average calories per purchase by 35 calories per transaction. That means that when you bought breakfast or lunch, it was 35 calories fewer after two years than it was before everything went into place.

Helen Osborne: Is that significant?

Dr. Anne Thorndike: Is that clinically significant or statistically significant?

Helen Osborne: Statistically. I’m not a researcher. I’m just wowed by the methodic way you go through this. I’m soaking that up. Thirty-five calories, that’s not a lot.

Dr. Anne Thorndike: It’s statistically significant, but you have to think about it. It’s 35 calories per transaction. That adds up over time.

What we were able to do was take the data of the total number of calories people purchased per quarter and then translate that into what we would expect that might result in if they made no other changes in their daily habits.

Assuming somebody is purchasing in the cafeteria and doing all the same things outside of that, then that reduction in calories would translate into a weight loss of about two kilograms, which is equivalent to a little less than five pounds, over three years.

Helen Osborne: Oh my goodness. Wow. That makes a difference.

Dr. Anne Thorndike: Yes. I’d like to just emphasize that this work is not to be considered a weight loss program. The goal is not necessarily that we’re trying to get people to lose weight. We’re actually trying to prevent weight gain.

Those calculations that I did are somewhat artificial because it’s really assuming that people don’t adapt in other ways. We’re not paying attention to their exercise level or what they’re eating outside of work.

But at the minimum, I feel very confident in saying that when people make these changes in the cafeteria, it’s probably helping them to prevent weight gain.

Helen Osborne: Interesting.

Dr. Anne Thorndike: We know from prior work that people gain one to two pounds per year, on average.

Helen Osborne: One of my questions is about the tone of this. Your interventions were the traffic light labeling. You did all the behind-the-scenes things. You did the traffic light labeling and you moved foods around and the availability of it.

It was really an educational nudge, perhaps, that you were giving people. You didn’t do any other programs about, “Don’t eat chips. Don’t eat cookies.” You didn’t do anything else on the side, did you?

Dr. Anne Thorndike: No, we didn’t. For those who were interested, we had booklets in the cafeteria that showed all the detailed nutrition information for every product. If somebody really wanted to know what the ingredients were for the red or yellow items, or if they wanted more information, it was there.

However, what we were doing was just nudging people, as you said, in the moment. People at work are in a rush, especially in a hospital. People are making quick choices.

What we wanted to do was help them in that moment. Maybe we could steer them away from an impulsive purchase that may not be consistent with what they actually want to do.

I think most people want to make a relatively healthy choice. For them, this program could be helpful.

Helen Osborne: That’s neat.

I’m not a big chain-food kind of gal, but do go into some of these stores and they now seem to have calories listed. Yours takes a different approach.

Can you talk about yours with the simple visuals and placement compared to, “If you want this salad, it has X calories, and if you want that salad, it has X plus 100 calories”? How does that compare as far as messaging and making a difference?

Dr. Anne Thorndike: I think that there are differences on many different levels. One thing is that our red, yellow, and green system actually takes into account more than calories. It takes into account the dietary quality.

The way that the algorithm is scored, there are pluses and minuses. Some of the pluses are whether it’s a fruit or vegetable or has whole grain or lean protein. Some of the negatives are calories and saturated fat content. We take into account all of those factors.

When you’re talking about just calories, you could have a food that’s mostly saturated fat for 100 calories versus a whole grain product that has 150 calories. You say, “I’m going to pick the 100 calories because it’s got fewer calories,” but actually, the dietary quality of that food is much lower.

Helen Osborne: Thank you for that. I know that your paper looks at that in more detail and you really went through rigor in evaluating all the foods.

Our listeners come from all over the world with all kinds of perspectives. What we have in common is that we all are interested in communicating more clearly about health.

What are your lessons for us? What can we take away from this amazing study and group of studies you’ve been doing for over a decade now?

Dr. Anne Thorndike: The first takeaway, I think, is that traffic light labels work. People do respond to it, and we’ve shown this in several studies. They actually change the way that they purchase.

Anecdotally, I’ve gotten a lot of positive feedback from people that I work with from all different backgrounds and levels, including people with M.D./Ph.D.s, as well as people who have lower education levels.

I think that the traffic light labels are effective because it doesn’t really require a higher education to understand the basis of what it means.

I think the other thing that is really effective is that we almost respond to traffic light labeling a little bit beyond just the intellectual piece. It’s almost an emotional reaction. When you see something red, you really feel like, “That’s not good. That’s not something I should do.”

I always say the reason why traffic light labels aren’t used more broadly for food labeling is because they work. There’s nothing more effective than the red light.

Helen Osborne: I’ve seen initiatives, and I’ve read about them sometimes, where grocery stores might start labeling their foods. Then that never seems to happen. Is it because it’s so effective?

Dr. Anne Thorndike: I’m not sure. You see a lot of grocery stores labeling things “healthy for you” or they might label the healthy items, which is great. If you’re looking to purchase a healthy item, you can find it. The problem is there are no reminders for the unhealthy items.

You can purchase your healthy items, but if you purchase the unhealthy items, there’s nothing saying, “This is unhealthy.” You can either be in denial about it, or you might not even know that it’s not a healthy product.

I really think that the most effective is labeling the unhealthy products to help us avoid them.

Helen Osborne: That’s a great tip. Never would have thought about that.

Traffic light labeling, you keep talking about colors. But not everybody can see colors. How do you work around that?

Dr. Anne Thorndike: The one story here is that when we first started to develop this program, we presented it to the president of the hospital. We were talking to him about the red, yellow, and green labeling and how great it was going to be. He said to us, “What happens if somebody is colorblind?” We all looked at each other like, “We didn’t think about that.”

The way that we handled it is that our color-coding is in the shape of triangles. Within a red triangle is an R that shows up that somebody who’s colorblind would be able to see. Then we have Y and G in the other ones.

Helen Osborne: Thanks for that.

I’ve done a podcast with the Medical Director from Consumer Reports that uses colored circles to label different qualities of an item. They ended up using different shading and ways to get around that, too. I will include a link to that on our Health Literacy Out Loud website.

Have there been any other surprises that you’ve gotten about this? Any pushback or any amazing breakthroughs in this labeling system?

Dr. Anne Thorndike: It’s been in place for 10 years. It’s highly utilized by people. No surprises.

I think the most reassuring thing to me is that people continue to say that it helps them and is effective.

People use all the cafeterias multiple times a day even, several days a week. We have these labels and choice architecture in all the on-site cafeterias. It’s really part of our culture.

We call the program Choose Well, Eat Well. The labeling and signage is all throughout every eating venue in the hospital.

Helen Osborne: Thanks. I like that you’ve said it’s been going on for so long. I can just imagine if I was working and eating there, I probably would just rely on those lights and indicators to know how to make my healthier choices each time I go to the cafeteria.

To me, listening to what you have done, it sounds so much like health literacy in action.

Thank you so much, Anne, for all you have done and researched so methodically and all your sharing with us about helping people make healthier food choices. Thanks for being a guest on Health Literacy Out Loud.

Dr. Anne Thorndike: Thanks so much for having me.

Helen Osborne: As we just heard from Dr. Anne Thorndike, there are many effective ways to communicate health messages. But figuring out what to do when and where is not always easy. For help clearly communicating your health message, please contact me at helen@healthliteracy.com.

You might also be interested in looking at my book, Health Literacy from A to Z, especially Chapter 10 that’s about the environment of care.

Health Literacy Out Loud podcasts come out every few weeks. You can get all the episodes automatically, for free, by subscribing at www.HealthLiteracyOutLoud.com. You can also find us on iTunes, Google Play, Spotify, iHeartRadio, RadioPublic, Stitcher and many other podcast apps.

Please help spread the word about Health Literacy Out Loud. Together, let’s tell the whole world why health literacy matters.

Until next time, I’m Helen Osborne.

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