7.2: Nutrition and Diet, by Lars Ove Dragsted
The New Nordic Diet - from Gastronomy to Health
The New Nordic Diet is a new food culture developed in 2009-13 with key emphasis on gastronomy, health, and environment. Major research in its effect on acceptability, behaviour and learning skills, and disease prevention have been conducted by the OPUS centre at the University of Copenhagen and the people behind the award-winning restaurant Noma in Copenhagen. This course will give the participants the opportunity to experience a healthy and palatable new food and eating concept diet “The New Nordic Diet” and an understanding of how food and diets can affect mental and physical health and ensure the foundation for a healthier life style for future generations with a regional based diet and food culture. In Denmark “the Nordic cuisine”, has expanded from food eaten at the award-winning Copenhagen restaurant Noma to home-made dishes of local ingredients of whole-grain rye bread, root vegetables, berries, fresh fish and seaweed. This course is also part of the EIT Health Programme
Investigate the New Nordic Diet – from Food to Health
In this last module's lectures we will concentrate on the health of the New Nordic Diet, focus on the effects published so far from four different studies and on the potential factors and foods affecting the outcomes.
7.1: Introduction, by Arne Astrup6:55
7.2: Nutrition and Diet, by Lars Ove Dragsted23:18
7.3: Industrially Produced Trans Fats and the New Nordic Diet, by Steen Stender13:51
Dr Arne Astrup, MD, DMSc.
Professor, Head of Department
Department of Nutrition, Exercise and Sports
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.
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.
You know that's a.
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, were defined 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, approximately.
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 their 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.
these 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 Nordiet 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 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.
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, high out 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 diet's recommendation level seems to be a major drive of this affect.
By reducing their 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 of 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.
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.