Palaeolithic diet decreases fasting plasma leptin concentrations more than a diabetes diet in patients with type 2 diabetes: a randomised cross-over trial
FontesV‑illalba et al. Cardiovasc Diabetol
Palaeolithic diet decreases fasting plasma leptin concentrations more than a diabetes diet in patients with type 2 diabetes: a randomised cross‑over trial
Maelán FontesV‑illalba 0 3 4
Staffan Lindeberg 3
Yvonne Granfeldt 2
Filip K. Knop 1
Ashfaque A. Memon 3
Pedro Carrera‑Bastos 3
Óscar Picazo 6
Madhvi Chanrai 5
Jan Sunquist 3
Kristina Sundquist 3
Tommy Jönsson 3
0 Calle José Betancort , 15, 35530 Teguise‐Lanzarote , Spain
1 Center for Diabe‐ tes Research, Gentofte Hospital, University of Copenhagen , Hellerup , Denmark
2 Department of Food Technology, Engineering and Nutrition, Lund University , Lund , Sweden
3 Clinical Research Centre, Faculty of Medicine, Center for Primary Health Care Research, Lund University , Malmö , Sweden
4 Calle José Betancort , 15, 35530 Teguise‐Lanzarote , Spain
5 Independent researcher , London , UK
6 NutriScience‐Education and Consulting , Lda, Lisbon , Portugal
Background: We have previously shown that a Palaeolithic diet consisting of the typical food groups that our ancestors ate during the Palaeolithic era, improves cardiovascular disease risk factors and glucose control compared to the currently recommended diabetes diet in patients with type 2 diabetes. To elucidate the mechanisms behind these effects, we evaluated fasting plasma concentrations of glucagon, insulin, incretins, ghrelin, C‑ peptide and adipokines from the same study. Methods: In a randomised, open‑ label, cross‑ over study, 13 patients with type 2 diabetes were randomly assigned to eat a Palaeolithic diet based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts, or a diabetes diet designed in accordance with current diabetes dietary guidelines during two consecutive 3‑ month periods. The patients were recruited from primary health‑ care units and included three women and 10 men [age (mean ± SD) 64 ± 6 years; BMI 30 ± 7 kg/m2; diabetes duration 8 ± 5 years; glycated haemoglobin 6.6 ± 0.6 % (57.3 ± 6 mmol/ mol)] with unaltered diabetes treatment and stable body weight for 3 months prior to the start of the study. Outcome variables included fasting plasma concentrations of leptin, adiponectin, adipsin, visfatin, resistin, glucagon, insulin, C‑ peptide, glucose‑ dependent insulinotropic polypeptide, glucagon‑ like peptide‑ 1 and ghrelin. Dietary intake was evaluated by use of 4‑ day weighed food records. Results: Seven participants started with the Palaeolithic diet and six with the diabetes diet. The Palaeolithic diet resulted in a large effect size (Cohen's d = −1.26) at lowering fasting plasma leptin levels compared to the diabetes diet [mean difference (95 % CI), −2.3 (−5.1 to 0.4) ng/ml, p = 0.023]. No statistically significant differences between the diets for the other variables, analysed in this study, were observed. Conclusions: Over a 3‑ month study period, a Palaeolithic diet resulted in reduced fasting plasma leptin levels, but did not change fasting levels of insulin, C‑ peptide, glucagon, incretins, ghrelin and adipokines compared to the currently recommended diabetes diet. Trial registration: ClinicalTrials.gov NCT00435240
Palaeolithic diet; Type 2 diabetes; Glucagon; Leptin; Lipotoxicity; Adiposopathy; Evolution
The metabolic syndrome represents a cluster of
symptoms including abdominal obesity, insulin resistance,
dyslipidemia, and high fasting glucose and blood
]. The condition is associated with a fivefold
increased risk of type 2 diabetes, which is characterized
by insulin resistance [
] and β-cell failure [
plays a prominent role in the pathophysiology of the
metabolic syndrome and type 2 diabetes [
an unhealthy diet with chronic caloric surplus induces
hyperinsulinemia leading to ectopic lipid deposition
(lipotoxicity) in the heart, liver, pancreas and muscle [
], increasing the risk of the metabolic syndrome, fatty
liver, fatty heart and type 2 diabetes .
Interestingly, insulin resistance has been suggested to
be a consequence and a protective mechanism against
]. Leptin resistance is a possible player
in the roadmap to the metabolic syndrome and type 2
], and it has been suggested that leptin can
protect against lipotoxicity [
]. Lipotoxicity can generate
α-cell insulin resistance resulting in
hyperglucagonaemia and increased hepatic glucose production [
]. It is
increasingly recognized that the recent (in an
evolutionary perspective) introduction of staple food groups such
as cereal grains, dairy products and refined sugars in
the human diet has occurred too recently for the human
genome to have completely adapted [
In a previous publication from this trial, we reported
significant improvements in glycated haemoglobin
(HbA1c), blood lipids, blood pressure, weight and waist
] along with increased satiety [
patients with type 2 diabetes consuming a Palaeolithic
diet, as compared to the officially recommended diet for
patients with type 2 diabetes (diabetes diet) [
The abovementioned pathophysiological changes
produce adaptations in other hormones and endocrine
axes. Therefore, our aim was to investigate if the
beneficial effects from a Palaeolithic diet could be tentatively
explained by associated changes in adipokines, glucagon,
incretins and ghrelin, and here we present new data on
the fasting levels of these hormones from our previous
] (Additional file 1).
Approval of the study was obtained from the regional
Medical Ethics Committee and the trial was registered at
ClinicalTrials.gov (Identifier: NCT00435240).
Patients with type 2 diabetes without insulin treatment
were recruited from primary health-care units in the
Lund area of Sweden. Details about inclusion and
exclusion criteria and patient characteristics (Table 1) have
previously been published [
]. All recruited subjects
were given oral and written study information prior to
signing a consent form to participate in the study and
were then further assessed for eligibility.
The study design and generation of random allocation
sequence have been reported in detail previously [
In short, the study was a randomised, cross-over, dietary
intervention study in which all eligible subjects were
informed of the intention to compare two healthy diets
and that it was not known whether one diet might be
superior to the other. After randomisation, there was no
blinding of dietary assignment to study participants, nor
to those administering the interventions or assessing the
outcomes. At study start, all subjects were randomised,
by use of opaque envelopes, to start with either a
diabetes diet designed in accordance with official
] or a Palaeolithic diet [
after randomisation, all subjects received oral and written
information about their respective initial diet
individually from diabetes nurses. After 3 months, all subjects
switched diets and received new oral and written
information about the new diet. Advice about regular physical
activity was given to all subjects.
The information on the diabetes diet stated that it aimed
to provide evenly distributed meals with an increased
intake of vegetables, root vegetables, dietary fibre,
wholegrain bread and other whole-grain cereal products, fruits
and berries, and a decreased intake of total fat with more
unsaturated fat. It was recommended that salt intake
should be kept below 6 g per day. The information on
the Palaeolithic diet stated that it should be based on
lean meat, fish, fruit, leafy and cruciferous vegetables,
root vegetables, eggs and nuts, while avoiding—as far as
possible—dairy products, cereal grains, beans, refined
fats, sugar, candy, soft drinks, beer and added salt. The
following items were recommended in limited amounts
for the Palaeolithic diet: eggs (≤2 per day), nuts
(preferentially walnuts), dried fruit, potatoes (≤1 medium-sized
per day), rapeseed or olive oil (≤1 tablespoon per day)
and wine (≤1 glass per day). The recommended intake
of the other foods was not restricted and no advice was
given with regard to the proportions of food categories
(e.g. animal vs. plant foods). The evolutionary rationale
for a Palaeolithic diet and its potential benefits have been
outlined previously [
] and detailed nutritional
compositions of the diets can be found in our previous report
An oral glucose tolerance test (OGTT) was performed in
the morning after obtaining venous blood samples and
measurements of blood pressure, weight and waist
circumference using standard methods [
] at the start of
the study, after 3 months (when switching to a new diet)
and at the end of the study (after 6 months). Samples
were collected in EDTA-containing tubes and
centrifuged for 10 min at 4 °C. Plasma was then aliquoted and
Data is presented as mean values with SD in brackets, unless stated
ACE angiotensin converting enzyme, GIP glucose‑ dependent insulinotropic polypeptide, GLP-1 glucagon‑like peptide ‑1
stored at −80 °C until analysis. Outcome variables in the
present study included fasting plasma concentrations of
leptin, adiponectin, adipsin, visfatin, resistin, glucagon,
insulin, C-peptide, GIP, GLP-1 and ghrelin.
Assessment of conditions of frozen blood samples
To assess the condition of the frozen blood samples we
compared new analyses of insulin to older ones. The
newly analyzed insulin values were on average 27 %
lower than older analyses and the standard deviation had
increased by 66 %. However, the Pearson correlation of
0.72 (adjusted R2 = 0.51) between new and old insulin
values for the same individual and time were highly
correlated (p < 0.0001).
The Bio-Plex pro™ human diabetes panel (Bio-Rad Inc.,
Hercules, CA, USA) a Luminex-based magnetic bead assay,
was used to quantify insulin, C-peptide, ghrelin, GIP,
GLP1, glucagon, leptin, resistin and visfatin and a separate
BioPlex assay was used to quantify adiponectin and adipsin
(due to different dilution factor) in plasma according to the
manufacturer’s instructions. Each run included controls of
known concentration for each cytokine and a blank.
The statistical power calculations were based on initial
primary outcomes of this intervention and previously
]. Data were analysed for normality (determined
by Q–Q plots and the Shapiro–Wilk test in SPSS) and
logarithmically transformed when necessary. If data did
not show reasonable normal distribution after logarithmic
transformation, the Wilcoxon matched pairs signed rank
sum test was used, otherwise a paired t test was used. To
analyse the difference between diets in their effects on
outcomes we compared the absolute values at the end of each
diet. In order to check for carry-over effects, t tests were
used to compare mean values of outcome variables for the
group starting with the Palaeolithic diet with those for the
group starting with the diabetes diet. In order to check for
period effects, t tests were used to compare the effects of
the first and second diets. We performed post hoc
analysis using bivariate correlations between the outcome
variables presented in Table 2 and outcome variables related to
glucose homeostasis and satiation. Bivariate correlations
were also performed between the outcome variables
presented in Table 2 and dietary variables. Outcome variables
with significant correlations were entered in Simple
Linear Regression. Significance was set at p < 0.05. All t tests
were two-sided. Due to multiple outcome measures
problem in this post hoc analysis a multiple outcome measures
correction was made using QuickCalcs online
provided by GraphPad Software (http://www.graphpad.com/
quickcalcs/interpretPValue1/). Statistical analysis was
performed with SPSS for Mac Version 20 (IBM SPSS Statistics
for Mac, Version 20.0, IBM Corp., Armonk, NY, USA).
All reported analyses are per protocol analyses on the 13
participants (3 women, 10 men) who completed the trial
(Fig. 1). Four subjects were excluded for the following
reasons: one starting with Paleolithic diet was wrongly
included with ongoing warfarin treatment, one starting
with Paleolithic diet was unwilling to continue due to
abdominal pains and bloating, one starting with
diabetes diet was excluded after developing leukemia, and one
starting with diabetes diet was excluded after developing
heart failure. Dates defining the periods of recruitment
and follow-up, and side effects have been previously
Individual characteristics regarding anthropometric
measurements, medication and outcome variables have
been reported in detail previously [
] and are
summarised in Table 1. The participants starting with the
Palaeolithic diet compared to those starting with the
diabetes diet did not differ at baseline for any of the outcome
variables (Table 1). No carry-over or period effect was
Data are mean ± standard deviation (95 % CI)
Significance tests are paired t test for normally distributed data and Wilcoxon matched pairs signed rank sum test for non‑normally distributed data
Significant p values are indicated by italics font
GIP glucose‑ dependent insulinotropic polypeptide, GLP-1 glucagon‑like peptide ‑1
a p for difference between diets
b Data non‑normally distributed (Wilcoxon matched pairs signed rank sum test)
c Old insulin values previously published
The absolute level of plasma leptin after the
Palaeolithic diet was lower than after the diabetes diet (large
effect size, Cohen’s d = −1.26; p = 0.023) (Table 2;
Fig. 2) [
]. When one outlier (more than 3 SDs)
was excluded, the mean difference of leptin after the
diets was normally distributed and the difference
remained significant (p = 0.031). However, due to
multiple outcome measures problem the probabilities
of having a p value less than 0.023 just by chance in
our dataset is 20.8 %.
The absolute level of glucagon at the end of the
Palaeolithic diet was lower than at the end of the diabetes diet
(moderate effect size, Cohen’s d = −0.51), but this
difference did not reach statistical significance (p = 0.089)
(Table 2; Fig. 2).
As previously reported, weight loss was significantly
greater (−3.3 kg) after the Palaeolithic diet than the
diabetes diet (p = 0.008).
No statistically significant differences between the diets
for the other variables were observed (Table 2).
Correlations and linear regression
In post hoc analysis of within-subject differences (value
after the Palaeolithic diet minus value after the diabetes
diet) we found that leptin correlated with fasting plasma
insulin (Spearman’s correlation 0.55, p = 0.049), grams
of dietary fat (Spearman’s correlation −0.66, p = 0.013),
percentage of dietary fat (Spearman’s correlation −0.55,
p = 0.049), grams of dietary saturated fat (Spearman’s
correlation −0.59, p = 0.033), grams of dietary fatty acid
C16:0 (Spearman’s correlation −0.57, p = 0.041), and
grams of dietary fatty acid C18:0 (Spearman’s correlation
−0.55, p = 0.049); glucagon correlated with area under
the curve (AUC) for insulin0–120 min (Pearson’s
correlation 0.94, p = 0.015), stimulated AUC insulin0–120 min
(Pearson’s correlation 0.55, p = 0.047), fasting plasma
insulin (Pearson’s correlation 0.63, p = 0.019), satiety
quotient for dietary glycaemic index per meal (Pearson’s
correlation −0.56, p = 0.045), dietary glycaemic load
(Pearson’s correlation 0.63, p = 0.021), dietary glycaemic
index (Pearson’s correlation 0.73, p = 0.005), dietary fatty
acid C20:5 (EPA) (Pearson’s correlation 0.58, p = 0.037),
Fig. 2 Fasting hormone levels after the Palaeolithic diet and diabetes
diet for leptin and glucagon. Data show individual differences in a
leptin and b glucagon after 3 months in response to the Palaeolithic
and diabetes diets. Significance of the difference is indicated by
asterisks (p < 0.05). NS non‑significant
dietary fatty acid C22:6 (DHA) (Pearson’s correlation
0.57, p = 0.04) and dietary vitamin B12 (Pearson’s
correlation 0.57, p = 0.041) (Table 3).
This small trial showed that a Palaeolithic diet decreased
fasting plasma leptin, but did not affect fasting levels of
insulin, C-peptide, glucagon, incretins, ghrelin and
adipokines significantly compared to the currently
recommended diabetes diet.
Weight loss interventions have been shown to decrease
leptin concentrations [
], and in our trial leptin
decreased only with the intervention that induced weight
loss, i.e. the Palaeolithic diet. However, post hoc analysis
revealed no correlation between difference in weight loss
and leptin after the diets (Spearman’s correlation 0.11,
p = 0.721).
Interestingly, genetic and in vitro studies indicate
insufficient adaptation of the human leptin system to a diet
based on cereal grains [
]. Therefore cereal grains
could hypothetically lead to leptin resistance and higher
leptin values. Our finding of lower leptin following a
Palaeolithic diet virtually devoid of cereal grains compared
to a diabetes diet with cereal grains supports this notion,
and could represent the mechanism behind our previous
findings of improved glucose control and blood lipids
 and greater satiety per calorie from the Palaeolithic
In our study there was a non-significant lower fasting
glucagon levels after the Palaeolithic diet compared to
the diabetes diet, which could be a result of the
amelioration of leptin sensitivity in the pancreatic islets. However,
this hypothesis should be tested in trials with adequate
Due to the small sample size, we were not able to
conduct a multivariate analysis adjusting for weight loss to
explore the independent effect of the Palaeolithic diet
on leptin and glucagon. Therefore, our results might be
explained by the weight loss produced only during the
Palaeolithic diet, as already mentioned.
Insulin plays a central role in type 2 diabetes, but
despite this we found no difference in fasting insulin
between the diets. Compared to baseline, there was a
significant decrease in insulin (p = 0.004 and 0.023, for old
and new insulin analysis, respectively) after the
Palaeolithic diet, which may be explained by weight loss.
Adiponectin appears to play an important role in type
2 diabetes due to its anti-inflammation, antiatherogenic,
and insulin-sensitizing properties [
], yet we found no
difference between the diets. However, there is some
controversy regarding the beneficial effects of adiponectin in
type 2 diabetes [
In the exploratory analysis there was a positive
correlation between change in fasting leptin and insulin, which
could be explained by the mechanisms discussed above
and recently reviewed by Nolan et al. [
]. This finding is
consistent with other studies where a positive correlation
between fasting leptin and insulin has also been shown
]. It has been shown that treatment with
recombinant human leptin does not improve insulin
sensitivity in obese patients with type 2 diabetes , contrary
to what happens in patients with severe leptin deficiency
]. This might support the notion that patients with
Pearson’s correlation ra
Spearman’s correlation rb Adjusted R2
Exploratory analysis was conducted to check for significant correlations between the outcome variables presented in Table 2 and outcome variables related to
glucose homeostasis and satiation. Bivariate correlations were also performed between the outcome variables presented in Table 2 and dietary variables. This analysis
consisted in bivariate Pearson or Spearman’s (for non normally distributed variables) correlation between within‑subject differences in outcome and dietary variables.
Normally distributed outcomes that were significant in Pearson’s correlation were entered into simple linear regression
a Pearson’s correlation for normally distributed variables
b Spearman’s correlation for non normally distributed variables
c p value for bivariate correlation and simple linear regression
type 2 diabetes suffer from leptin resistance.
Interestingly, within-subject differences in fasting leptin
correlated negatively with the intake of total fat (in grams and
percent) and C16:0 and C18:0 fatty acids. These results
are consistent with a randomised controlled trial where
a low-fat diet lowered leptin levels more than a high-fat
]. On the other hand, in a well controlled study
leptin levels were higher with a low-fat diet than a
lowglycaemic index or very low–carbohydrate diet [
Other trials found no effect of fat restriction on leptin
]. This inconsistency in results may be due to
differences between individuals in gene variants related
to leptin physiology .
Comparison with findings from other studies
In a previous trial from our group, leptin decreased
significantly during Palaeolithic and Mediterranean diets,
respectively, with no differences between diets, but after
exclusion of one outlier with a high grain intake in the
Palaeolithic diet group there was a significantly greater
decrease in leptin in this group [
]. Interestingly, in the
same study there was a strong correlation (Pearson’s
correlation 0.50, p = 0.008) between change in leptin and
intake of cereals [
]. Nevertheless, contrary to our
previous finding there was no correlation in the data
(Spearman’s correlation 0.22, p = 0471). Additionally, data from
the present trial indicated that the Palaeolithic diet is
more satiating than the diabetes diet [
], consistent with
another trial from our group [
]. Other randomised
clinical trials have shown beneficial effects of a
Palaeolithic diet compared with other healthy diets on
cardiovascular risk factors [
] and body fat [
]. A recent
systematic review and meta-analysis, where these studies
were included [
], showed that a Palaeolithic diet
improves some components of the metabolic syndrome
more than the healthy control diets .
The Mediterranean diet has been the focus of several
publications regarding its role in the metabolic syndrome
and type 2 diabetes [
]. A systematic review and
metaanalysis showed that the Mediterranean diet was superior
to control diets for all components of the metabolic
syndrome . Another systematic review and meta-analysis
concluded that the Mediterranean diet decreased HbA1c,
but not fasting glucose, more than control diets but not
more than the Palaeolithic diet [
]. An important
consideration with respect to the characteristics of
Mediterranean and Palaeolithic diets concerns their resemblance.
Both emphasize a high intake of whole unprocessed foods,
specifically: fruits, vegetables, fish, nuts, and olive oil, while
the limitation in the intake of wholegrain cereals and
legumes in the Paleolithic diet is the main difference. In light
of the role that inflammation and oxidative stress might
play in glycaemic control in type 2 diabetes [
mechanisms behind the beneficial effects of the
Mediterranean and Palaeolithic diets could be attributed to their
antioxidative and anti-inflammatory capacity [
both the Mediterranean diet and the Palaeolithic diet share
common features that render them as healthy options in
patients with type 2 diabetes, and represent a step forward
for an optimal human diet.
Vegetarian diets are regarded as a healthy option for
western diseases as well. A recent systematic review and
meta-analysis investigated the effects of a vegetarian diet
on glycemic control in type 2 diabetes [
], resulting in
better HbA1c, but not fasting glucose, than control diets.
None of the the included trials tested a vegetarian diet
against a Palaeolithic or Mediterranean diet.
Importantly, a systematic review and meta-analysis
assessed the effect of various diets on glycemic control in
type 2 diabetes [
]. The results indicate that all the diets,
namely low-carbohydrate, low-glycaemic index,
Mediterranean and high-protein diets, improved HbA1c
compared with their respective control diets. Consequently,
the best dietary approach for the management of type 2
diabetes continues to be a matter of debate.
Limitations of the present study
A limitation of this study, as with most other dietary
trials, is the lack of blinding after randomisation. To
minimise this problem, all study participants were informed
of the intention to compare the effect of two healthy diets
for the treatment of type 2 diabetes and that it was not
known which one would be superior. Also, written
information with dietary advice, food recipes and behavioural
support were similarly formulated for both diets. The
difference in weight loss, macronutrient composition
and glycaemic load between the diets precludes a
definite conclusion about the specific role of different food
choices on the endocrine system.
The results of this study should be interpreted with
caution for other reasons as well. First, we have the
limitation of multiple outcome measures problem and the
probability of type I error for leptin in our study is 20.8 %.
Secondly, the outcomes generated from this post hoc
analysis represent exploratory investigations; the primary
outcomes have been previously published. Lastly, this
study has a small sample size which precludes us from
performing adjusted multivariate analysis. This is
specially relevant for weight loss because it decreased only
during the diabetes diet and the difference after the diets
was 3.3 kg (p = 0.008). As a result, since weight loss is a
principal driver of improved leptin sensitivity we are not
certain about the independent effect of the diets on the
We show that a Palaeolithic diet results in significantly
lower fasting plasma leptin, non-significantly lower
fasting plasma glucagon concentrations as well as weight
loss, compared to a standard diabetes diet. Human
beings are well adapted to food groups similar to those
found in the Palaeolithic era during our evolution, and,
hypothetically, the lower leptin and glucagon levels could
indicate that deviations from this template is not optimal
and could explain our previously reported findings on
glucose control, blood lipids, blood pressure and satiety.
But the small sample size of the present study makes it
impossible to perform adjusted multivariate analysis and
the observed weight loss after the Palaeolithic diet may
also contribute to explain our results. Long-term and
adequately powered trials investigating the effects of
Palaeolithic diet are warranted.
Additional file 1. Supporting data set. Data set supporting our results on
hormones (adipokines, glucagon and incretins), post hoc analysis and pre‑
viously published outcomes (worksheet ‘Data set’). Each row numbered
1‑13 in first column ‘Person‑ID’ corresponds to data from one participant.
Each column heading contains a variable name stating what individual
mean has been measured, in what unit and whether on the Paleolithic
diet, diabetes diet or if it is the difference between the two diets (DeltaPd,
value during Paleolithic diet minus value during diabetes diet). The vari‑
able names and their description are listed below.
AUC: area under the curve; GIP: glucose‑ dependent insulinotropic polypep‑
tide; GLP‑1: glucagon‑like peptide ‑1; HbA1c: glycated haemoglobin; OGTT:
oral glucose tolerance test.
All the authors fulfil the following conditions: (a) substantial contributions to
conception and design, acquisition of data or analysis and interpretation of
data; (b) drafting the article or revising it critically for important intellectual
content; and (c) final approval of the version to be published. All authors read
and approved the final manuscript.
The authors are grateful to Professor Birgitta Hovelius and Dr. Kristina Haara for
their participation in designing the study, to Lilian Bengtsson and Lena Kvist
for technical assistance, and Anna Hedelius for excellent technical support.
We are also very grateful to Amreeta Buxani for helping in the review of the
Availability of data and materials
The dataset supporting the conclusions of this article is included within the
article (and its additional file). Additional file 1.
The authors declare that they have no competing interests.
Ethics approval and consent to participate
Approval of the study was obtained from the regional Medical Ethics Commit‑
tee and the trial was registered at ClinicalTrials.gov (Identifier: NCT00435240).
All recruited subjects were given oral and written study information prior
to signing a consent form to participate in the study and were then further
assessed for eligibility.
The study was funded by Crafoordska stiftelsen, Region Skåne and Lund
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