 Hello everyone. I'm Adam Drunowski. I'm Professor of Epidemiology at the University of Washington in Seattle and I'm here remotely to talk to you about yogurt, a sustainable food. So my presentation today has to do with sustainable dietary guidelines. What are they? Increasingly, we are interested in the nutrient value of foods, but also in their environmental footprint. So the sustainable dietary guidelines take us from nutritious foods to sustainable, affordable, nutritious foods. And there are different ideas that I want to introduce to you today. So what are sustainable diets? They are defined by the Food and Agriculture Organization of the United Nations as diets with low environmental impact, which continue to contribute to food and nutrition security. Sustainable diets are protective and respectful of biodiversity, they are culturally acceptable, they are economically fair, they are affordable, and they are respectful of the environment. The definition developed and adopted by the Food and Agriculture Organization of the United Nations is very complicated and clearly it was written by committee. There is one thing that you need to remember that sustainability of foods does include their nutritional value. In other words, nutrition and health are at the core of dietary sustainability. In fact, there are four dimensions of sustainability. As you see on this slide, first of all you have nutrition and health, then you have the environment, then you have societal value, and then you have economics and affordability. So people very often think that sustainable diets are the one with lowest environmental impact on the land and water and air. But in fact, all those four domains are included in the definition of sustainability. So think of sustainability as integral to nutrition and health. Sustainable foods and sustainable diets need to be nutritionally adequate, affordable, culturally appropriate, and environmentally sound. All of those things together. There is however a problem. All those four dimensions cannot be met simultaneously. We must choose, and we do not like to make choices, but choose we must. So if you look at this slide, you will see that nutrition and health and economics are not completely compatible because nutrient-rich foods are more expensive. It is the empty calories that are cheap. When we look at nutrition and the environment, as you will see later, it is the same problematic relationship. More nutrient-rich foods have a higher environmental footprint and are more costly in terms of land and water use and carbon dioxide emissions. But at the same time, there are more nutrient-dense, and we cannot do without them. And then we move on to societal issues. On one hand, climate change will affect our diets. On the other hand, our diets will affect climate change. So what we eat will have an impact on the climate and the weather, and the weather and catastrophic weather events can change what we eat. So as you choose your next meal, think of the consequences. Is it healthy for you? Is it healthy for the planet? Or is it both? And here we come to the science. Trying to identify those foods which give you the maximum of those points at the same time. Which foods in our food supply are nutrient-dense and sustainable and affordable and help create shared social value. In other words, deeply, profoundly integrated into our society. So, we come to dairy products and yogurt. And here what I want to do is to talk about a few metrics. We are scientists. We look at metrics and measures. We measure things. And there are ways of measuring sustainable foods, and we've adapted some of those metrics to the case of yogurt. So here we have nutrient density. Nutrient profiling has been mentioned in one of the previous presentations. We have econometrics affordability and the affordability of dairy products in terms of calcium per penny. Then we have issues of which foods are planet-friendly. We measure the impact on the environment in terms of greenhouse gas emissions. And increasingly, we're beginning to look at the water needs of growing or producing different foods. And then the societal value, we have a number of metrics of shared value and looking at the value to society of dairy farming and dairy production. So let me deal here with just three of those. Nutrient density, environmental impact and affordability. And what I have for you today is some examples of those metrics and also specific case histories from three or four countries, the United Kingdom, France, but also Turkey and Mexico. Dairy production is a global issue. Yogurt is sold worldwide. And I want to show you specifically metrics and measures developed from multiple countries coming together. So the first issue. How do we measure nutrient density of food? I will not go into great detail beyond telling you that nutrient density is typically measured in terms of nutrients per calorie. What we are trying to do is to separate the foods which are energy dense from those that are nutrient rich. As you see on the next slide, some foods are energy dense, many calories per gram between four and nine calories per gram and often contain a limited amount of key nutrients per calorie. And then on this slide on the top left, you have foods which are low in calories but high in nutrients. So here we separate foods which are energy dense from those that are nutrient rich. Energy dense foods have more calories than nutrients. Nutrient rich foods have more nutrients than calories. And on this slide, you pretty much see which foods are which. I will go on to the next slide and show how we adapted a nutrient profiling system from the United States for the specific case of Turkey. And so on the left, you see the nutrient rich foods score which I call NRF 9.3 because it contains or is based on nine beneficial nutrients and three nutrients to limit. The nine beneficial nutrients that we usually include in nutrient profiling models are protein, fiber, vitamin A, vitamin C, vitamin E, calcium, iron, potassium and magnesium. To be able to do a fairly complex nutrient profiling model, you need good databases. But we simplified that model for the specific case of Turkey. So we developed a 6.3 algorithm with fewer nutrients, just six on the beneficial side. Protein, fiber, vitamin B12, vitamin C and vitamin D, as well as iron and calcium. And then we have the same three nutrients to limit, saturated fat, total sugars and sodium. In some cases we use total sugars, in other cases we use added sugars. The results come out pretty much the same. So what I want to show you in the next slide is how the Turkish snacks were placed into categories based on the nutrient profiling algorithm. Take a look at this slide. On the left, we have empty calories. In the middle, we have full calorie foods with considerable nutritional value. And then on the right, we have very, very low energy density nutrient rich foods. As you see here, these are some vegetables, cucumber and fresh fruit. But a lot of the nutrient rich foods that children eat are going to be in the middle column. And this column does include apples, bananas, apricots, milk, flavored milk, yogurt, and some nuts and almonds. Very typical in Turkey. So the nutrient density score from left to right and then energy density on the vertical axis. And notice that this score was the basis for recommendations in Turkey for the recommended school snacks. Notice here that yogurts and buttermilk and almonds and some nuts are in a green zone to be consumed on a regular basis. The empty calories, by contrast, are going to be on the bottom among the foods not recommended to be consumed every day. So this is one example how nutrient profiling of nutrient density can be used for policy development and recommendations for snacks. Just a bit more science. Those snacks in Turkey met some interesting requirements. For example, notice here on this slide that we're showing energy density on a horizontal axis and calories preserving on a vertical axis. So here we're showing that plain milk and yogurts and grapes and tomatoes were low energy density in terms of calories program but also well below 150 calories preserving. So low energy density, high nutrient value. And the next slide shows you that the dairy products were unique in that these were the only snacks that were rich in calcium. So you have two things, high nutrient density, low energy density and high content of calcium in just those few last slides. Now, we then move to the new topic. Nutrient density we already have. The next point is how do we measure environmental impact? And it's much the same metric because now we look at the carbon footprint per calorie or the carbon footprint per nutrient content. So we do very much the same thing as before. We need to have nutrient composition data for foods. We need to have dietary intake data and then we attach the carbon cost to each of the foods in the nutrient composition database. So one example I'll show you here today is from France and we were able to attach carbon costs to the food and we were able to attach carbon costs, greenhouse gas emissions to a number of foods sold by the French supermarket chain Casino that allows us to calculate the energy density of the foods, the nutrient density of the foods, but also the carbon cost of the foods and the carbon cost per calorie and per nutrient. This is very interesting because you see how each food has its own environmental cost. And of course diets composed of those foods can be differentially sustainable from the standpoint of the environment. So these are data now from the Casino project. Casino is a large group of supermarkets in France with international impact. They have supermarkets everywhere else in the world as well. These are the values for greenhouse gas emissions obtained for about 450 foods sold in the supermarket. We obtained nutrient composition from the French government SQL nutrient composition database and we aggregated the foods into approximately 34 categories. So this allowed us to analyze the nutrient content of foods and their carbon footprint for each of those food groups separately. So this slide shows you the carbon cost in terms of greenhouse gas emissions per 100 calories for a given category of foods. Notice that we start with processed fruits and vegetables, then go to meat and meat products, then meat and dairy, then grains and then sweets. Paradoxically it is actually sweets and sugar which have the lowest environmental impact, but they're also least nutritious. So there is going to be a balance and a trade-off between environmental footprint and nutritional value. Notice also that the carbon cost can be separated out into agricultural production, processing, transportation, packaging and in-store. So if the product needs to be refrigerated or frozen in-store, that adds to the greenhouse gas emissions. So some products will have high agricultural processing, but lower in-store costs, but others such as frozen vegetables may have very high in-store costs. But in both cases, sweets and sugar have a remarkably low carbon cost, but as I keep saying, they also provide you with the lowest nutritional value. So let's take a look now at the carbon cost of nutrient density. What I'm showing you now is the casino data as yet unpublished, showing the nutrient density score on a horizontal axis and carbon dioxide emissions per 100 calories on a vertical axis. So notice that as we go from left to right, the foods are becoming more nutrient rich and more nutritious. So on the left, you see sugar and candy and sweetened beverages and chocolate. Low carbon dioxide emissions, but low nutritional value. And the problem is that as the nutritional value of food goes up, so does the carbon cost. Unfortunate but true. So that at some point you need to say at what time is the higher carbon cost offset by the higher nutritional value. And then you got to ask yourself how do we know that and who decides. Pay special attention to the position of milk and yogurt right here on this continuum, higher in nutrient density but also higher in carbon cost than sweetened beverages or candy or sugar or some cereals. There is a trade-off to be made. If we move to the next slide, this shows you the carbon cost of calories. Again, note the separation between the animal products on the left, cheese, organ meats, poultry and eggs and meat dishes and more cheese and milk and yogurt. High nutritional value, higher carbon cost and then the foods on the bottom right, high energy density, plenty of calories and low carbon cost. With some exceptions such as potatoes or fortified ready to eat cereals and some oils, many of these foods will be empty calories. Low carbon cost and low nutritional value. Again, trade-offs to be made. The next slide shows you the carbon cost of protein. Providing various populations with high quality protein at an affordable cost and with environmental sustainability is going to be the main challenge of the 21st century. What are those sources of sustainable protein? Will it be beef, will it be pork, will it be fish or will it be dairy products? So notice here that fish and eggs and poultry give you more protein but they also have higher carbon cost than many sources of vegetable protein. Again, pay special attention to the location of milk and yogurt picked out here in red. They are high in protein and relatively lower in carbon cost than are many other options. Then moving on, I just want to show one nutrient and that is calcium. So what you see here on a horizontal axis is the calcium content in terms of calcium per hundred calories. On a vertical axis, again, you see the carbon cost. Notice that in terms of calcium per hundred calories, milk is completely of the scale way out some place and then yogurt comes very close followed by cheeses and then pizza. Those are the major sources of calcium in the diet. So again you see here the carbon cost of calcium and of course you can see that yogurt and dairy products are well positioned in terms of overall nutritional value, calcium and their overall environmental impact. So now we come to the final component of my presentation because we said that the foods need to be nutrient rich. They need to be environmentally friendly or planet friendly but they also need to be affordable. They cannot be too expensive. So how do we measure affordability of foods? And again it is the same metrics except now we attach monetary cost to the nutrient profile. So what we do is use the same methods to rate foods based on the calories or the nutrients that they provide per penny. Again we're interested more in nutrients than in calories. Having cheap calories is not what we want. If you want cheap calories the place to go to is going to be again sugar. So we attach monetary cost to foods and now I'll show you some American data from NHANES National Health and Nutrition Examination Survey. We look at nutrient composition data, we look at price data and we try and figure out the affordability of various foods in terms of nutrients per penny. So this is a slide I have shown before. We are looking at energy density on the vertical axis and we're looking at energy cost in terms of dollars per thousand calories on the horizontal axis. This is a logarithmic scale meaning the cost increases tenfold as you go from left to right. So notice that the cheap sources of calories are going to be sugar and cereals and pasta and yes there are some nutritious foods in there including nuts and milk and beans, good nutrition at low cost. The dairy products fit very comfortable towards the lower middle. Notice the yogurt and milk and dairy products in the middle section and then as we go to the right this is where we see salad greens, fresh fruit, fresh fish, seafood and so on. This is the hierarchy of food prices that we have and again we can reverse this scale to show you that nutrient rich foods generally cost more. So when I reverse this scale still based on American data for close to 1400 foods we now see that if we now substitute nutrient density on a vertical axis some of the nutrient rich foods are more expensive. Again the more expensive foods are going to be the fresh fruits, the vegetables and the seafood and dairy products fit comfortably in the middle section. Again the lower cost foods, the sweets, the sweetened beverages, some of the fats on the bottom left are lower cost and lower nutritional value. So these are the data from the NHANES surveys in the United States showing that some lower cost foods can be nutrient poor and some of the nutrient dense foods can be associated with higher cost. So again when it comes to behavioral economics of diet choice we need to select foods which are nutrient rich and the same time are affordable for all. Again here you see that within the circle you have beans, legumes, nuts, seeds, milk and milk products and eggs giving you good nutritional value for an affordable cost. This type of food prices hierarchy is not found only in the United States. We actually found the exact same data in Mexico, a low and middle income country. These data were presented to the Mexican Ministry of Health last year. Mexico now has a tax on snacks and sodas and the data were showing that the relationship between nutrient rich foods and energy density in Mexico was the same as we have in the US. Notice that nutrient rich foods of course are vegetables, fruits, skim milk, fish, beans and yogurt and again the nutrient rich foods in Mexico tend to be more expensive. So the same hierarchy of prices holds. This slide shows you energy density of foods and the energy cost in Mexican pesos per hundred calories. So poultry, fish, seafood, fresh meat, vegetables, fruit, more expensive, milk and yogurt, cheaper, rice, tortillas and tamales and lard and sugar, cheaper still. So at some point as you go towards lower cost you start losing nutritional value. It is all about compromises. These foods are nutrient rich and the foods on the other end are nutrient poor. So this kind of brings me to my conclusion. What we are doing increasingly is trying to integrate the nutritional value of different foods with their environmental impact. This is the famous double pyramid put together by Barilla Foundation and we're looking now at the nutritional pyramid on the left and the inverse pyramid of environmental impact on the right. We're trying to identify foods which are nutrient dense, affordable, planet friendly and steeped in history creating continued shared value. Again pay attention to the middle of the pyramid. It's all compromises and again notice the position of dairy products right there on the nutritional pyramid and low down on the environmental pyramid. Nutrient dense, affordable and planet friendly at the same time. And two reports based on data from France and the United Kingdom have come to the same conclusion. This is a nice slide from my friend and colleague Dr. Nicole Darmont working in Marseille showing that fresh dairy products were part of affordable diets. This is now modeling of what diets provide most nutrients for least monetary cost. These are data from France based on the French database INCUT2. Conclusions from my other friend and colleague Dr. Jenny McDermott from Aberdeen are showing that yogurt is part of a diet with a low carbon footprint. This was a very beautiful study looking at the carbon footprint of different type diets showing that carbon footprint could be reduced without eliminating meat, without eliminating dairy and making a special provision for yogurt during multiple meals per day. So this is a rare example of Franco-British complete agreement and we hope there will be more of that in the future. So to conclude we have the specific case of dairy products in yogurt which are going to be classified through various metrics as being nutrient rich, affordable, environmentally friendly and a part of nutrient rich sustainable diets. Thank you very much.