[MUSIC] Hello, my name is Lars Ove Dragsted. And I'm a professor in biomedicine and nutrigenomics at the laboratory of Biogenetic Food and Health, which is situated at the Department of Nutrition, Exercise, and Sports, NEXS, University of Copenhagen. At NEXS, where I work, we are about 280 scientists and technical staff, and some 150 are working on many different aspects of nutrition. Most are housed in this building on the Frederiksberg campus. Diet and other lifestyle factors have become major drivers of morbidity and mortality in most parts of the world. With aspects of Western food culture as some of the main suspects. It is therefore a focus area in nutritional science, to search for improvements in local or global food culture that could affect health. The health effects of Nordic foods are currently a highly investigated subject, and investigations are ongoing. However, the Nordic diets are not exactly the same in investigations. Nordic diets may be defined by the Nordic nutritional recommendations issued by an expect group under the Nordic council administrators. Or they may be defined jointly by the nutritional experts and other food professionals as in the case of the new Nordic diet NND. Both diets include high intakes of fish, whole grain cereals, low fat dairy products, fruit, berries and vegetables. However, the NNR, and NND, differ in terms of scope; with NNR being solely nutritional, while the NND also takes Nordic identity, palatability, sustainability into consideration. The NND, therefore, includes a high intake of foods from wild landscapes, at sea and land, and is mainly organic. In contrast, the NNR includes non-local foods, especially seafoods and plant products from foreign areas. Since they are absolutely okay from a nutrionial point of view. However, it should be stressed that the NND is designed as a prototype regional food culture and could be imitated with a combination of healthy and tasty local foods in any part of the world. In the table here you can see the force that is. NORDIET, SYSDIET, SHOPUS. And the open school bus project. You've heard about the last two in the previous lectures in this course, and as you can see, the four studies differ in several ways. And these are important to know and to keep in mind when we try later to compare the study outcomes. The two first studies were according to the Nordic Nutrition, Nutritional Recommendations, issued by the Nordic Counsel of Ministers. The last two were according to the U-not Nordic diet, which on top of the Nordic nutritional conditions also demands certain system, sustainability and palatibility of the diet. The first of the four step is Nordiet, had 86 volunteers who had basically, slightly increased LL cholesterol, above 3.5 millimoles per liter. It was done in adults. And in half of the volunteers who had diet according to the Nordic nutrition recommendations, the foods were provided. Whereas in the controls, the foods were as they usually buy them in their own supermarket. The Nordiet study was conducted in the city of Balnes, in the Uppsala area in Sweden. In the Sysdiet study, the diet was given in a restricted way so that they were not allowed to have a weight loss. The volunteers, 166 in total, were recruited from all five Nordic countries. They had [COUGH] an increased BMI, above 27 but below 38. And then they had two additional conditions related to the metabolic syndrome. That could be high blood pressure, a high triglyceride level, an increased tolerance to glucose, and a, decreased high density lipid protein cholesterol. These two fat, first studies have been published already. The Shopus studied with 146 volunteers, had their foods from a supermarket, that was set up at the Copenhagen. University. They were recruited based on their waists, which in males had to be above 94 centimeters round the waist, and for females, above 80. It was also in adults only. The last study, the school bus project, was slightly less than 800 children from different schools in the greater Copenhagen area. They were recruited. They were just normal school children who signed up for the study. And they had the diet ad libitum. And they, as you've heard in previous lectures, were strongly involved in how the diet was prepared and served. And were monitored for a range of outcome measures. Conducting human trials is not trivial. There are many pitfalls and challenges on the effort on logistics. And are considerable, as you have already seen in the previous lectures. One of the greatest challenges, like in all biology, is that most effects in our body are strongly connected, yet at the same time, we differ individually. A large number of volunteers are therefore needed for statistically valid results. However, the more volunteers you have in a study, the more difficult it is to ascertain that they are all compliant. Compliance means whether they exactly follow the diet and other instructions they have been given. Most volunteers are probably non-compliant at some times during the trial and this weakens the overall effect that may be seen. Compliance is one of the largest challenges in human dietary studies. I'll therefore discuss this aspect as a quality parameter during this lecture. In this figure, you can see the timeline in the bottom. The study stops. You have recruited your per, your volunteers, and at this time you take the baseline samples. You also divide them into the Nordic food group and Habitual diet group. Then later after six weeks, you take again samples and of' course measure, an, (INAUDIBLE) And, this, this time, you also have all the time, all the data that you need in order to make this statistical comparison. So, when all this has been done and all data have been delivered. You are allowed to get the code and do a statistical, the statistical analysis and compare the two groups. Were there difference, yes or no? All foods in the Nordic food groups were provided to participants in the Nordiet study. Throughout and compliance in both groups was evaluated by dietary interviews before and at the end of the intervention. However, no objective compliance measures were used. The comparison of the two groups at the end was done by standard statistical procedures for study of this design. The dietary changes recorded by the interviews in NORDIET were quite marked as seen in the table. You can see in the left hand panel, the different variables related to nutrition. The first one in, in the upper panel, you can see the different diets, the control diet and the Nordic diet, at baseline and after six weeks. There is also something called p, which is the statistical comparison. As you can see, for instance, the energy was more or less the same in the control diet at base line. And after six weeks, whereas with the Nordic diet, you can see that volunteers who were allowed to eat as much as they wanted, took less food and had a lower energy intake. Then you can see the P values for the control diet is relatively high 0.31. Whereas for the Nordic diet it goes very low, below 0.001, which means that it's highly statistically significant. For all these variables that you can see the protein the carbohydrates, the dietary fiber. a specific fiber, the bet beta-glucans. And also for salt intake. And polyunsaturated fats. Fat quality. You have significant differences at between the two diets in during the intervention trial. Only alcohol did not differ between the two groups. The Nordiet was not large, but the effects were comparably very marked. First of all, a weight loss was induced by the NNR. The intervention also affected blood pressure, insulin levels, and insulin sensitivity. Lipiprotein cholesterol and cholesterol ratios as seen in the table. However, it was found that the effects on insulin and blood pressure were secondary to the induced weight loss. Again in this table, you can see the characteristics, that have been measured in the study that I just mentioned. And you can see the Control diet and the Nordic diet and the difference between them measured by statistical evaluation. You can see, for instance, that body weight was changed by a very trivial amount in the control diet. Whereas in the Nordic diet, there was a three kilogram decrease in body weight after six weeks. This is highly statistically significant even in the small sample. This the same way you can see for a range of the the markers here that they are effected statistically significantly. Usually for statistical significance, you use a cutoff of 0.05. So, whenever you see a value in the P column which is below 0.05, this means that we regard the result as different between the two groups. Several of the markers affected are risk markers for cardiovascular disease. This includes insulin sensitivity, blood pressure and markers of bad. That's the LDL and good HDL lipoprotein cholesterol. The ratio between good and bad lipoprotein cholesterol, as well as the ratio between the core proteins apolipoprotein B and A1, are particularly important markers also. As it can be seen, the cardiovascular risk mark is targeted here. Insulin, blood pressure and lipoproteins are favorably affected by the NNR diet in hypercholesterolemic volunteers in the NORDIET studied, study. But only cholestorol was affected after correction for weight loss. In the second Nordic, Nordic study, with NNR, Sysdiet was comparably larger with 156 completers and had a longer duration, up to 24 weeks. Several samples were taken at randomization at 12 weeks and again at termination at 18 or 24 weeks. Volunteers were instructed by dieticians to follow one of the two dietary regimens. And key foods were provided to the volunteers in both food groups. Compliance was measured by a food diary that was filled in by the volunteers. You can see here, again, a timeline. Again, you can see the randomization and the healthy Nordic diet group and the control group. So this is a different graphic from the previous, but it's the same design, just another way of showing it. You can see the randomization time and you can see the 12, and week, midterm, and the 18 or 24 weeks termination time. You can also see that the four day food diary was was given to the participants at several time. Point zero to 12 and so on weeks. In this figure, you can see the SYSDIET dietary changes. In the left panel, you can again see the different nutrients. And on the top panel, you can see the different time points and groups. Beware that in this table, you see the healthy diet first and the control diet afterwards. Then followed by the changes and the statistical test outcome. You can see that most of the variables evaluated here had a significant change with only sugar intake and folate not changing significantly. As you can see, there's no difference in the energy intake between the two groups. As I already explained, the participants in this study were not allowed to lose weight during the intervention. Despite the marked dietary changes reported, the health outcomes of intervention were comparatively small. And included mainly a small improvement in cholesterol and lipoprotien ratios as shown in the next figure. You can see that only the ratios where significantly change, where it's the individual Apo B, Apo A one and I can tell you also for HDL and LDL cholesterol were not significantly changed. This result is in accordance with the Nordiet study and indicates that improved cholesterol may be achieved without weight loss, by improving the quality of the diet. Another result was related to the marker of inflammation. The interleukin 1 receptor antagonist, IL-1RA. In this figure, you can see that over time, there was a change in IL-1RA, so that especially in the control group, there was an increase, whereas in the intervention group, there was no change. This led to an overall large difference, difference between the two groups at the end of the intervention, indicating that perhaps the control diet, specifically, was less favorable, favorable, than the intervention diet. Interleukins are signaling peptides affecting bodily functions. Much like hormones. The IL-1 system is well known to be affected acutely in infections. But it's also associated with chronic inflammation in diabetes, and in diseases of the joints. The results observed in Sysdiet, therefore, deserves attention in other studies. So far, this particular inflammatory marker has not been assayed in the other Nordic food studies. Back to B studies. The SHOPUS study has been already presented in this course. This is also a parallel RCT, running for six months. But about the size of the SYSDIET with 164 volunteers completing the study up until 26 weeks. Diet was tightly monitored by the supermarket system, where volunteers selected their food and where compliance was assured before they left the supermarket. As you can see in this graphics that you have probably seen before you have a picture of the supermarket and you can see the timeline. This time, the, there, there are not two timelines, one for each group, but it represents both groups at the same time. And you can see the times when the different samples were taken. As previous, previously shown, the contrast between the two diets was clearly shown in the recorded foods. So SHOPUS was very successful, successful in achieving a changed intake of the targeted foods. In the next graph, is shown the relatively, the relative intake of nutrients per unit energy. Since the energy intake was lower for the NND group, the graph is not directly comparable with the table shown previously for the other studies. You can see in this figure, that you have also been presented for, previously that most of all the, the nutrients are changed. And they are, higher with the NND for the healthy foods, such as, protein. And the healthy fats, such as the monounsaturated, here called MUFA, and the polyunsaturated, here called PUFA. and lower for some of the other variables, such as added sugar and total fat. A major affect after 26 weeks was weight loss with NND compared with the control group. So, an, analogy to the NNR study in Uppsala, that is the NORDIET study, weight loss is induced when NND was introduced. The Nordic dietary recommendations therefore seem to be a major drive of this affect. By reducing the energy intake. But it may additionally be affected by some of the specific foods as well. As previously detailed in this course, there was a favorable effect of the NND on glucose, but not on insulin or insulin sensitivity, except in pre diabetics. And, the effects were explained mainly by the weight loss. Systolic and diastolic blood pressure also decreased. However, this was not solely explained by the weight loss. Triglycerides were affected in SHOPUS as opposed to the other studies and again this effect was only partially explained by the weight loss. In contrast, the effect on cholesterol was mainly tribute, attributable to the weight loss in SHOPUS. Again, no effect was observed on the inflammatory marker, CRP. The school bus project had a crossover design and was conducted in healthy children with direct delivery of food to the NND group, which gives strong compliance in this group. You've, as you have seen previously in, in this, graphics, you have the timelines and you have the crossover, shown by two different colors. So, this school bus went out to the different schools and served the food for the children involving the, to a large extent. We do not have outcomes from this study yet, so it cannot be discussed further here. We can summarize the outcomes published so far in the tables shown here. Weight loss was clearly affected when individuals with high cholesterol and or body weight allowed to eat as much as they like during the Nordic diet. dietary recommendations, using mainly local foods. Diabetes-related markers, like insulin, glucose, or homa, are clearly affected when there was a weight loss, but not when body weight was kept elevated by forcing volunteers to eat extra food, as in SYSDIET. However, there are some discrepancies between the studies. In the NNR studies, the first two, independent and weight loss, the Nordic diet seemed to affect blood lipids in a favorable direction with a better ratio between the good and the bad cholesterol. In the NND study, this was not the case. But blood pressure was affected independently of body weight. In a recently published sub-study from SYSDIET, blood pressure was measured more carefully. And in this study, the Nordic diet significantly reduced blood pressure compared with the control diet, despite lack of weight loss. So weight loss may actually be affected more generally by NNR as well as NND. Independent on weight loss. The effects on inflammation need further analysis. The C-reactive protein, CRP, was not affected by NNR or NND, but IL-1RA was strongly affected in the SYSDIET study. This marker needs to be analyzed in the other studies as well. The question is now, what could be the specific factors affecting these parameters? Apart from the effect of a lower energy intake, this question is of course not easy to answer, based on studies with whole diets. However, we can look at other studies where only a single dietary effect has has been changed, in order to evaluate the effect of each of these outcomes. For instance, increased protein intake has been shown previously to affect appetite and reduce weight gain. Is therefore possible that it could also lead to weight loss. Very high fiber intakes, as seen in these studies, have also been shown such affects simply because the volume of food becomes large. So a positive energy balance becomes difficult to maintain. This is all, all, this is also in accordance with observation in SYSDIET, that volunteers had difficulties eating so much that they could keep their weight. Fish intake, as well as plant foods, have been shown to reduce blood pressure in many studies. Reduced salt intake, clearly, has a similar effect, but did not seem to explain the lower blood pressure, at least in the NNR studies. Fish, at least fatty fish, also helps increase HDL cholesterol, while whole grain and fruit and vegetables typically reduce total cholesterol and LDL cholesterol. The combination of these foods therefore could favorably affect the ratios between bad and good cholesterol. Another point is that energy is consumed in the form of foods, of course. Some of these foods might be associated with negative health outcomes, and hence, these outcomes are improving when less food is ingested. For instance, the intake of snacks and of heated foods may have been reduced more in the Nordiet, diet, and superstudies, where compliance was more tightly monitored than in SYSDIET. Reduced diabetes risk factors may therefore be secondary to some of these factors rather than calories. This also remains to be evaluated. In conclusion, Nordic diets reduce body weight in overweight or otherwise metabolically compromised individuals. They also seem to favorably affect markers of cardiovascular disease, independently of weight loss, while reducts, while reductions in diabetes risk factors seem to depend mainly on weight loss. We have no indications yet that these effects are due to any particular Nordic food or food component. The antiinflammatory and blood pressure lowering factors are particularly interesting and could be related to cooking practices or to specific food constituents. Further research will be needed in order to answer these important questions. And overall, the overall effects would most likely be seen also with healthy diets designed in any other part of the world, based on a local food culture, just like it has been shown previously for the Mediterranean diets. So the perspective of a healthy Nordic diet is that the healthy and sustainable diet could be devised in all countries around the world. Thank you for your attention. [MUSIC]
