Adam Drewnowski, PhD, MA. Director of the Center for Public. Health Nutrition. at the University of Washington,

Transcription

1 Adam Drewnowski, PhD, MA Director of the Center for Public Health Nutrition at the University of Washington,

2 Ladies and gentlemen, goodafternoon. My presentation today will deal with the issue of nutrition economics and the complex links between foods, incomes, and health. And let me begin by saying how privileged I am and how honored I am to be following on this podium my very distinguished colleague Professor Walter Willet. As you will see, our presentations will be exactly complimentary. We differe somewhat in our approaches. Let me tell you how. Nutritional epidemiology tries to link diets and chronic disease. The focus is on macronutritients, micronutrients, dietary ingredients or even specific foods. Hence, you hear stories about soda and diabetes, transfats and adverse health outcomes, fruits and vegetables and better health. In each case, a nutrient, an ingredient, an antioxidant is linked to a health outcome, adjusting for inconvenient covariants such as income. Now, social scientists take a very different view. They say it is impossible or at least very hard to separate the person from the food they eat. It is very difficult to separate the foods from the food supply and therefore culture. So, waiting to take their place alongside nutritional epidemiology in the study of diets and health are sociology, economics, and behavior. So, the emphasis here is not so much on what is on the plate. The emphasis is on what is around the plate and around the plate are social factors, socioeconomic factors, social class and incomes. So, my presentation today will deal with the economics of nutritional choice and I will take similar approaches to delineate the problem. First of all, yes, there is a global health crisis. One of the reasons we have the problem that we do is that the global diet has become very rich in calories. And it is becoming relatively poor in nutrients and that is the global problem of hidden hunger. It was referred to earlier this morning. It is a major phenomenon even in wealthy industrialized societies. Our people are getting too many calories and not enough nutrients so that malnutrition different forms of malnutrition can occur even in high-income societies. And I think there is an economic cost to that and there is an economic reason. One reason is that the empty calories cost less and some not all some nutriet-rich foods cost more. So, healthy eating for many people is becoming too expensive it is becoming too stressful and it is really so to speak, not on the menu. So, the theme of this meeting cultural revolution in nutrition. So, I say the story of sociology and economics and nutrition economics is now coming to the table. So, let the cultural revolution begin. And there is a story here as well. Within each group of society there are people who seem to be able to get a healthy diet at low cost. We have become very interested in those people. We call this an example of 'nutrition resiliance.' Resiliance is the capacity to withstand stress. So, the question we have is can resiliant people eat better for less? First of all, who are those people? What is their behavior? What are their attitudes? What do they think and what foods do they buy? And in the United States one group characterized by nutrition resiliance are actually Mexican Americans and we think that ethnic eating habits have much to do with getting healthy diets at low cost. So, this idea of nutrition resiliance hold it in mind. We'll come back to that later. And also I want to share a personal experience. Every time I come to a different country, Turkey included, I go to supermarkets. I go to farmers' markets and I take food prices into account. So, these are some photographs I took last year in a department store in Yokohama, Japan. Fruit are not a traditional part of the Japanese diet. The beautifully packed fruit that you see are really gifts. They are not for everyday consumption but if you look at prices in Yen, you can see that each beautifully packed bunch of grapes is close to 4,000 Yen and that is 40 dollars. That would be 100 Turkish lira for a bunch of grapes. And so contrast Japanese prices with prices in a fruit market in Ankara, where I was two years ago and again I went to a farmers' market and looked at prices and the beautiful tamatoes and the prices are much less than they are in Japan.

3 So, nutrition economics has absolutely everything with the type of diet that you have, the quality of the foods you buy, and the health outcomes. And this idea is certainly not new to me. It has a long and involved and distinguished history I should say. Because the first book linking food health and incomes was written by Professor Sir John Boyd Ohr in the United Kingdom in What he was finding in 1936 was that a large part of the British public was too poor to afford a healthy diet. So, John Boyd Ohr wrote a signal report on food health and income. He later became the first director general of the food and agriculture organization of the United Nations and received the Nobel Peace Prize in 1949 for his nutrition research. So, as you see linking food health and incomes has a long and distinguished history. Now, what Professor Sir John Boyd Ohr was able to show was the socioeconomic gradient in the consumption of different types of foods. What he was doing for the very first time was to stratify the population by income. That was at the time very novel and open to criticism. Now, not everyone does it. We do but in most cases in the United States, nutritional data are broken out by race, ethnicity, gender and age and never by social class. One reason is that official in the United States social class does not exist so you cannot study what does not exist. So, this social gradients that you see here are the consumption of fruit, the consumption of vegetables and the consumption of fish rose with incomes. Exactly as it does in the United States of today. It absolutely has not changed in 80 years. We still have the same social gradient in a consumption of vegetables, fruit and fish. So, you may wonder whether or not the benefits of fresh fruit have to do with antioxidants or are they more to do with the fact that people who consume them are rich? And have health insurance and are thinner and healthier and again going back to England of 1936, you see that potatoes and lard and sugar had no socioeconomic gradient and in fact now in the United States sugar has become what's called an 'inferior good' meaning that sugar and regular sugared soft drinks are primarily consumed by the poor. So, you have gradients going this way and that way and it is impossible in studies of nutrition and epidemiology to account for it all. And those gradients have not really shifted in the past 80 years we see the same thing in France and elsewhere. There is a major issue of cost when it comes to the selection of healthy diets. And the question why can't the poor eat better was also asked in 1936 in the United Kingdom the person who asked it was no less than George Orwell, the famous British writer responsible for such books as In The Road to Wigham Pier, George Orwell was commenting on a letter written to The New Statesman by someone who was very middle class who said for four shillings a week I can have a diet which has whole grain, fresh fruit and dried fruit. And the question was why can't the poor do the same instead of spending their money on tea and white bread and jam and a whole lot of sugar just like the diet of the poor of today. George Orwell's comment, which still holds is that lowincome people don't eat that way. They want something satisfying. They want something tasty. They want something good. A millionare said George Orwell can live on brown bread and raw carrots but the working class person will not. What they really want they want more sugar and they want more fat and of course that is what we have today and that is the problem that we face. Interestingly enough, the current dietary guidelines for Americans is advising us to eat more plant foods. As you see on the slide, every single food on this slide is a plant food. Not an animal product in sight. These are all plant foods. So, what are the reasons? And my colleague Barbara Rolls will deal with some of the motivations in trying to get children to consume vegetables and fruit. Why don't the poor eat like this?

4 This picture is actually from a brochure produced by the United States Department of Agriculture. This was a suggested dinner for a low-income family benefitting from food assistance. So, take a look at this plate. This was a nutritious plate for food assistance recipients a satisfying dinner. First of all, first question is how many calories on the plate? Some of you are probably nutrition experts but I'll give the answer to you the number of calories on this plate is 300 calories. 300 calories is not a lot of calories for dinner. The second question I have is what did it cost to buy? Because mushrooms, red peppers, brussels sprouts, green beans you have to buy those in large amounts. So, I actually went to a store and bought those foods. It was around 10 dollars for 300 calories. Again, remember, that the food assistance in the United States is 42 dollars per person per week. This took 45 minutes to prepare. This was not a balanced meal. And it was composed of foods which are not eaten that often. When you look at the frequency of consumption of various foods in the United States, French fries will win out over brussels sprouts anytime. The second problem that sometimes we have with the dietary guidelines is that some of those foods that are being portrayed are aspirational. This is not the reality for most people. Yellow peppers cost 3 dollars and 99 cents per pound. Fresh tomatoes, fresh salmon very expensive, cherry tomatoes again this is the cover of the dietary guidelines for Americans and the reality is that food assistance benefits are 42 dollars per person per week. On the right you see another brochure which talks about behavioral economics and diet quality of nutrition assistance program participants notice if you will the peeled kiwi and the peeled oranges and I suppose you can live well on nutrition assistance provided you have domestic help. And so this is the issue. Sometimes the issue of cost is more perceived than real and sometimes it is real. And the question is if by paying a bit more for the food that we eat will we realize nutrition benefits? And the answer is of course we will and then as I will tell you later on, nutrition resiliance may have a lot to do with cooking at home. So staying at home and cooking a meal an important part of culture that's where culture comes in may in fact be the way to have a high-quality diet at low cost. And then occassionally you see pictures of celebrities who undertake a week's diet for 29 dollars. I will not mention the celebrity but you can Google this on the web. This was a foodbank challenge, challenging people to eat all their meals for a week for the total cost of 29 dollars. So, this is the market basket of one person as a nutrition scientist I went and calculated the calories the nutrients and the cost and noticed that here you have a very nice, very nutritious plant-based diet, high nutrient density but what you have here is under 900 calories per day, which is clearly inadequate for any adult person. So, you can have nutrients, you can have calories but this diet is not adequate ot live on. In fact, a better choice for the amount of money not to be hungry probably would have been more fat and more sugar and more starches because at least that prevents you from being hungry. So, let's now move on to some underlying scientific concepts which are behind all this reasoning. The first very important concept which my colleague Barbara Rolls will talk about later on is the energy density of foods. And knowing about energy density is absolutely fundamental. The second concept is nutrient density of foods. So, when energy density of foods is calories per gram, nutrient density is nutrients per calorie. And then affordability, a key concept of my presentation, is either calories per unit cost or nutrients per unit cost.

5 What are you getting for your money in terms of calories and in terms of the key nutrients. So, just a few things. What I've plotted on this slide is energy density in calories per hundred grams on a horizontal axis and water content on a vertical axis because water content and energy density of foods are actually inversely linked. Vegetables and fruit have volume and are heavily hydrated. Fats and oils and dry grains and nuts and seeds have no water and their energy density is high. So, energy-dense foods are dry predominantly. But dry foods are cheaper per 100 calories. In fact, always say that the most expense ingredient in any food is water. Because water means cold chain storage, perishability, low-cost foods are going to be fats and oils and sugars and grains. And this is the way it is, so energy-dense foods can promote overeating but they're also very cheap, which means overeating does not cost you extra and then the problem that we have is some cheaper foods, not all, some cheaper foods can be tasty but nutrient-poor. I say some because there are some energy-dense foods which are not expense and those will be nuts and beans. And some grains they are energy-dense, nutrient-dense and inexpensive. The problem sometimes is people don't like them. So, now you have this complication of nutrient density, energy density, cost and pallatability all of which have to be taken into account. So, what we have been doing is establishing nutrient profiles of food. So, we have been rating foods based on their nutrition content. And the nutrient profiling has a taken off. And nutrient profiling is being used by different groups on one hand regulators want to use it to regulate marketing and advertising on the other hand industry has been using nutrient profiles to improve the quality of their food portfolio. So, some companies are using nutrient profiling schemes to reformulate foods to take out the added sugar, to take out the fat, reduce the salt and see if the nutritional profile of the food improves. And you can use those kind of techniques to profile individual foods, you can use them to profile menus on meals and you can use them to profile total diets. So, very briefly I'll show you that we have created such a score. It's called the nutrient-rich foods index. It's available on the web because it's in public domain. It's free for anyone to use. We looked at nutrients to encourage, protein, fiber, vitamins and minerals. We looked at nutrients to limit. Saturated fat, added sugar and sodium. We calculated an algorithm and then we started rating foods based on their nutritional value plotted against energy density. So, this is how things come out. So, on the horizontal axis now you see nutrient density of different foods. Notice that not all fruit and not all vegetables are equal. Some are better than others. One of George Orwell's books Animal Farm is about equality how some animals were more equal than others. And some vegetables are more equal than others. So, here you have vegetables and salad greens to the right. You have dried fruit and french fries towards the left because of the fat. And then the energy density of course goes up. And then you have grains going all the way from fortified cereals on the right to cake and cookies on the left. You have dairy products where the nutrient content goes left to right depending on the saturated fat. And then you have nuts and beans and eggs and meat and fish. Note the high energy density of nuts. But relatively good nutrient content then you have the fats and then you have sweets and soft drinks and sugar and when you add everything together it looks like this. And notice that this is a continuum. I never say good foods to the right, bad foods to the left. It all depends. It's an absolute continuum. And there are foods of differing nutritional value within every food group. So, nothing is inherently good nothing is inherently bad it all depends and when you start looking at the total dietary pattern, everything changes because then you start looking at the nutrient quality of the total diet. One problem is of course as I was saying before that some nutrient-rich foods can cost more per 1,000 calories. So, if you want to fill up as cheaply as possible without caring about nutrition and you don't care about the nutrients jus the calories, you know where to go. It's going to be the foods to the left. The foods to the right which are much more nutrient rich are also going to be associated with higher cost. But as I said not always and not for everybody what is this nutrition resiliance and who are the people who are making the right decisions? How can you have foods which are both nutrient rich and lower cost? Can this be done? And so here what we have been doing is looking at following dietary guidelines and looking at the cost of following dietary guidelines.

6 The dietary guidelines for Americans suggest that we eat more of whole grains and vegetables and fruit and milk and so on and more fiber and potassium and vitamin D and less saturated fats, refined grains, added sugars and sodium. And every five years, the United States Department of Agriculture comes back with a diet quality index. It's called healthy eating index. And this is a measure of compliance with dietary guidelines. Now the index is not perfect. The Harvard Index is viewed by some as an improvement. The healthy eating index does the best job it can in measuring compliance with dietary guidelines, which in themselves can be problematic. But be it as it may, what we have been doing is looking at the cost of the higher scores of the healthy eating index. So, in a very unique study what we were able to do is to attach natoinal food prices for 6,000 foods obtained from the US Government with dietary intake data from the national nutritonal and health examination survey and we were able to calculate the cost fo the healthy eating index for tens of thousands of people. So, these are now healthy eating index scores by diet cost. These are the components of the healthy eating index from the bottom up. Total vegetables, greens and beans, total fruit, whole fruit as distinguished from fruit juice, whole grains, dairy and so on. And the five bars represent progressively more expensive diets. And clearly as the diets gets more expensive, the diet is also high quality, which means the more expensive diets to the right in the top quintile of cost have more vegetables, more grains, more total fruit, more whole fruit and less added sugar and added fat at the top. The higher scores mean better compliance. And we get a very similar data and we get very similar data for men in every case the healthy eating index cost is associated with higher diet quality. The two seem to be completely tied for the population. And our question was what if we were to identify a group of people for whom diet quality goes up and the cost does not? So, here we started focusing on meals at home and the time spent cooking. So, one of the studies already published by my colleague Pablo Monsivite, who is now at Cambridge, we found that time spent cooking and preparing food was actually linked to higher quality diets and more vegetables and more fruit. And then in the most recet analysis, we found that the frequency of cooking meals at home was linked to higher diet quality score without a corresponding increase in cost. So, here we now have data from the Seattle Obesity Study showing an increased in diet quality but this time on the horizontal axis you see the frequency of eating at home. So, people who are eating and cooking at home more frequently had higher-quality diets and they were not paying any more because there was no corresponding increase in diet cost. So, this is where culture comes in because cooking and eating together at home is a part of social bond. My French sociologist colleagues tell me that eating is a personal act that is performed in public. By eating with other we share. By eating with other we control what we eat. A lot of the overeating that we see is people eating alone in front of the television set. So, in fact the French have a word called 'commancalité' which doesn't quite exist in English. It means coming together to the table to share. And this is where the sociology of nutrition makes a very important contribution in my mind as important as the contribution of nutrition epidemiology. The behaviors and the social bonds and the choice behaviors all come together to give us healthy diets at lower that expected cost. So, I say let the cultural revolution begin. And the cultural revolution in nutrition is a theme I set alongside nutrition transicion on which I have also published with my colleague Barry Popkin. The nutrition transicion is the shift from the traditional grain-based diets to a dietary pattern with more animal foods and more added sugar and more added fat. And the problem here is that the low cost of empty calories makes them very attractive to the world's poor. And this is why we have hidden hunger. Too many calories not enough nutrients. And yet such things as cooking at home, making good choices, making good affordable choices, helping people to identify healty, affordable foods we can bring about this cultural revolution. And interestingly enough the word 'cultural revolution' has some connotations of the class struggle. So, the challenge before us in this revolution that we're embarking on today is to make sure that healthy foods are affordable and equally available to all. Thank you.