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February 2018 | Volume 5 | Article 81
ORIGINAL RESEARCH
published: 09 February 2018
doi: 10.3389/fnut.2018.00008
Frontiers in Nutrition | www.frontiersin.org
Edited by:
Giuseppe Grosso,
NNEdPro Global Centre for Nutrition
and Health, United Kingdom
Reviewed by:
Alessandra Lafranconi,
Università degli studi di Milano
Bicocca, Italy
Eda Bozkır,
Università Politecnica delle Marche,
Italy
Alice Rosi,
Università degli Studi di Parma, Italy
*Correspondence:
Louise Seconda
l.seconda@eren.smbh.univ-paris13.fr
Specialty section:
This article was submitted to Nutrition
and Environmental Sustainability,
a section of the journal
Frontiers in Nutrition
Received: 31August2017
Accepted: 22January2018
Published: 09February2018
Citation:
LacourC, SecondaL, AllèsB,
HercbergS, LangevinB,
PointereauP, LaironD, BaudryJ and
Kesse-GuyotE (2018) Environmental
Impacts of Plant-Based Diets: How
Does Organic Food Consumption
Contribute to Environmental
Sustainability?
Front. Nutr. 5:8.
doi: 10.3389/fnut.2018.00008
Environmental Impacts of Plant-
Based Diets: How Does Organic
Food Consumption Contribute to
Environmental Sustainability?
Camille Lacour1, Louise Seconda1,2*, Benjamin Allès1, Serge Hercberg1,3,
Brigitte Langevin4, Philippe Pointereau4, Denis Lairon5, Julia Baudry1 and
Emmanuelle Kesse-Guyot1
1 Equipe de Recherche en Epidémiologie Nutritionnelle (EREN), Centre d’Epidémiologie et Statistiques Sorbonne Paris Cité,
INSERM (U1153), INRA (U1125), CNAM, Université Paris 13, COMUE Sorbonne Paris Cité, Bobigny, France, 2 Agence de
l’Environnement et de la maîtrise de l’Energie, Angers, France, 3 Département de Santé Publique, Hôpital Avicenne, Bobigny,
France, 4 Solagro, Toulouse, France, 5 Nutrition Obésité et Risque Thrombotique (NORT), Aix Marseille Université, INRA 1260,
INSERM UMR S 1062, Marseille, France
Background: Studies investigating diet-related environmental impacts have rarely
considered the production method of the foods consumed. The objective of the present
study, based on the NutriNet-Santé cohort, was to investigate the relationship between a
provegetarian score and diet-related environmental impacts. We also evaluated potential
effect modifications on the association between a provegetarian score and the environ-
mental impacts of organic food consumption.
Methods: Food intake and organic food consumption ratios were obtained from 34,442
French adults using a food frequency questionnaire, which included information on
organic food consumption for each group. To characterize the overall structure of the
diets, a provegetarian score was used to identify preferences for plant-based products
as opposed to animal-based products. Moreover, three environmental indicators were
used to assess diet-related environmental impacts: greenhouse gas (GHG) emissions,
cumulative energy demand (CED), and land occupation. Environmental impacts were
assessed using production life cycle assessment (LCA) at the farm level. Associations
between provegetarian score quintiles, the level of organic food consumption, and envi-
ronmental indicators were analyzed using ANCOVAs adjusted for energy, sex, and age.
Results: Participants with diets rich in plant-based foods (fifth quintile) were more likely
to be older urban dwellers, to hold a higher degree in education, and to be characterized
by an overall healthier lifestyle and diet. A higher provegetarian score was associated
with lower environmental impacts (GHG emissionsQ5vsQ1= 838/1,664 kg CO2eq/year,
−49.6%, P<0.0001; CEDQ5vsQ1=4,853/6,775 MJ/year, −26.9%, P<0.0001; land
Abbreviations: GHG, greenhouse gas; CED, cumulative energy demand; LCA, life cycle analysis; Q, quintile; PUFA, polyun-
saturated acid; MUFA, monounsaturated acid; SFA, saturated fatty acid.
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Lacour et al. Environmental Impact of Diet
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INTRODUCTION
According to the Food and Agricultural Organization (FAO),
adopting sustainable diets at a global level is urgently needed
(1). Sustainable diets should include a large share of ecologically
based, local and minimally processed products and limited con-
sumption of animal products. Sustainable diets are also healthy
in terms of both nutrition and sanitary quality (1). Regarding
the environmental aspects of a sustainable diet, a shi from
current dietary patterns toward more environmentally friendly
habits appears necessary. Environmentally friendly habits include
reducing the consumption of animal products and increasing the
consumption of plant products (2). Indeed, livestock is consid-
ered to be responsible for 18% of the greenhouse gas (GHG)
emissions from anthropogenic sources at the global level, and this
pattern is comparable at the country level in France (3). More
specically, beef and milk production represent 41 and 20% of
the emissions from livestock, respectively (3). Livestock requires
substantial energy for multiple activities such as the production
of feed, breeding activities, production and spread of fertilizers,
electricity use, and operating costs of farm buildings (4). Intensive
livestock production is also responsible for a large part of the loss
in biodiversity due to important land use for grass and feed crops
(5). Conversely, extensive livestock farming is suggested to have
positive eects on biodiversity. Studies investigating these issues
have consistently reported that decreasing the consumption of
animal products would have a considerable benecial impact on
the environment (6, 7).
e FAO also mentions that alternative modes of produc-
tion may be important to the promotion and development of
sustainable diets. Organic agriculture is dened as a system that
relies on ecosystem services rather than external agricultural
inputs (8). It is generally considered a more environmentally
friendly production model that enhances the quality of soil
leading to higher plant and fauna diversity and lower nitrate
leaching. Nevertheless, disparities in agro-ecological practices
still remain (9–12). e sustainability of organic food systems
and their ability to feed the global population have oen been
questioned mostly due to their usually lower crop yields (13,
14). It is now largely recognized that organic production
requires less energy inputs than conventional systems (15–17),
although benets in terms of GHG reduction are not straight-
forward (18). Moreover, rm conclusions about conventional
and organic systems are moderated by the functional unit
(18–20).
Despite ample literature on environmentally sustainable diets,
few studies have considered both dietary patterns and produc-
tion modes. It is, therefore, of interest to study both parameters
simultaneously to be able to estimate the extent to which organic
food consumption aects diet-related environmental impacts.
It is of considerable interest to consider both plant-based and
organic foods, which are consumed by vegetarians in Western
countries (21).
A review of Aleksandrowicz etal. revealed that the change
from a traditional western diet to alternative dietary patterns
(e.g., Mediterranean, vegetarian, or vegan) normally provides
benets for both individual health and the environment (22).
e reductions in environmental footprints should generally be
proportional to the magnitude of the restriction of animal-based
products (22). Despite lower environmental impacts when com-
pared to omnivorous diets (23), vegan or vegetarian diets are still
not culturally accepted, particularly in France, where meat-based
meals and cheese are an integral part of the traditional diet (24).
In this context, the provegetarian score (25), which characterizes
diets by the level of plant and animal product consumption, and
not directly by animal product exclusion, is highly relevant in the
French environment.
us, the rst objective of this study is to estimate diet-
related environmental eects according to the provegetarian
score. Second, we focused on studying the moderating eects of
organic food consumption according to the level of plant-based
food consumption. Data are based on a large sample from the
NutriNet-Santé study within the framework of the BioNutriNet
project, which enabled us to collect food consumption data and
environmental data on both organic and conventional products.
MATERIALS AND METHODS
Study Population
e subjects are adult volunteer participants from the prospec-
tive NutriNet-Santé cohort, which was launched in May 2009 in
France. e NutriNet-Santé study has been previously described
in detail in another study (26). At inclusion in the cohort and
yearly thereaer, the participants completed three 24-h ran-
domly distributed accounts that were provided over a period of
15days. ey were also asked to complete a set of questionnaires
about their sociodemographics, anthropometrics, health status,
and lifestyle characteristics. Participants were also regularly
invited to complete complementary questionnaires. In 2014,
participants were asked to provide information on their organic
occupationQ5vsQ1=2,420/4,138m2/year, −41.5%, P<0.0001). Organic food consump-
tion was also an important modulator of the relationship between provegetarian dietary
patterns and environmental impacts but only among participants with diets rich in plant-
based products.
Conclusion: Future field studies should endeavor to integrate all the components of a
sustainable diet, i.e., both diet composition and production methods.
Keywords: provegetarian dietary pattern, organic food consumption, eco-friendly farming, diet-related
environmental impact, sustainability
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food consumption as well as their motives and attitudes toward
organic foods.
Data Collection
Sociodemographic and Lifestyle Characteristics
e yearly updated inclusion questionnaire provided data on
sociodemographic characteristics including age, sex, highest
achieved degree (lower than high school, high school, or post-
secondary graduate), location (rural community, urban unit with
a population smaller than 20,000 inhabitants, between 20,000
and 200,000 inhabitants, or higher than 200,000 inhabitants),
and monthly income per household unit (lower than 900 euros,
between 900 and 1,200 euros, between 1,200 and 1,800 euros,
between 1,800 and 2,700 euros, and higher than 2,700 euros). e
monthly income per household unit was obtained by dividing
monthly income by consumption units (CU); the rst adult in the
household represents 1 CU, other persons older than 14 represent
0.5 CU, and other persons younger than 14years represent 0.3
CU (27).
is set of data also provided lifestyle characteristics such as
physical activity (measured by the IPAQ–International Physical
Activity Questionnaire) (28–30), smoking status (never, former,
and current smoker), and alcohol intake (never, moderate, or
frequent drinker). Moderate alcohol consumption was dened
as an intake lower than 20g/day for women and lower than 30g/
day for men (31).
Dietary Data and Organic Food Consumption
Between June and December 2014, participants were asked to
complete an optional organic food semi-quantitative frequency
questionnaire (Org-FFQ) based on the original validated
Nutrinet FFQ (32). e Org-FFQ collected information on con-
sumption frequencies (yearly, monthly, weekly, and daily units)
and portion sizes for 264 food and beverage items over a year. e
total food intake was estimated by multiplying the consumption
frequency and portion size for each item. To estimate the share
of organic food consumption in the diet, for each item in the
Org-FFQ, participants indicated how oen they consumed that
item in an organic form. Organic food frequency was assessed
using a 5-point ordinal scale, “never,” “rarely,” “half of the time,”
“oen,” and “always,” which were weighted as 0, 0.25, 0.5, 0.75,
and 1, respectively, and yielded an estimate of the proportion of
organic food consumed in an individual diet. e contribution of
organic food consumption to the diet was calculated by dividing
the total organic food intake (g/day) by the total food intake (g/
day) excluding water. is ratio was multiplied by 100 to obtain
the contribution of organic food as a percentage of weight.
e development of the Org-FFQ and sensitivity analyses
for the allocation of arbitrary weightings has been described in
another study (21).
e NutriNet-Santé food composition database (33) was
used to estimate daily nutrient intake independently of the
production method. To assess the nutritional quality of dietary
patterns, two indicators were assessed at the individual level: the
PANDiet (based on the probability of adequate nutrient intake
for 24 nutrients) (34) and the mPNNS-GS (modied French
national nutrition and health programme (Programme National
Nutrition Santé), with the PNNS-guidelines score based on the
adherence to the PNNS recommendations excluding physical
activity) (35).
Environmental Data
e methodology for the environmental evaluation of indi-
vidual diets is described in detail in the Presentation S1 in
Supplementary Material. Data were collected via the French
diagnostic tool DIALECTE (36) using the life cycle assessment
method (LCA) (37, 38) at the farm level (from agricultural inputs
and animal feed production to harvest). To date, DIALECTE is
the only French database that covers such a large panel of data for
both organic and conventional agricultural products. is study
considers the three environmental indicators available: (1) GHG
emissions were estimated including carbon dioxide, methane
and nitrous oxide emissions and were expressed in kilogram CO2
equivalent per day. (2) e cumulative energy demand (CED)
indicator was dened as the consumption of renewable and
unrenewable energy in megajoules per day according to the CED
method (39). (3) Finally, land occupation was dened as the area
in square meters needed per day. e environmental database
includes information on 62 raw agricultural products based on
measurements from 2,086 farms in France and on 30 raw agricul-
tural products based on information from the literature. Among
these farms, 46% follow certied organic agricultural practices
(as dened by European regulations).
For each participant, organic and conventional food consump-
tion was multiplied by the environmental impact of each product
to estimate the impact of the overall diet for each participant.
Construction of the Provegetarian Score
e provegetarian score was developed to reect the proportion
of plant-based food consumed in a diet (25). Components of the
provegetarian score include seven vegetable food groups and ve
animal food groups (25) (Table S1 in Supplementary Material).
Sex-specic adjustment for total energy intake was made for
the consumption of each food group using the residual method
(40). Energy-adjusted, sex-specic quintile values for each plant
component were calculated by allocating 1 to 5 points. For animal
food groups, the quintile values were reversed (from 5 for the rst
quintile to 1 for the h quintile). Finally, the provegetarian score
was obtained by summing the quintile value of each vegetable
food group and the reverse quintile value of each animal food
group. e score ranges from 12 (low consumption of plant food)
to 60 (high consumption of plant food).
Data Treatment and Statistical Analysis
Among the 37,685 participants who completed the Org-FFQ,
participants with missing sociodemographic data or aberrant
data were excluded (N=1,390). To detect under reporting and
over reporting, energy requirements were calculated for each
individual using physical activity level (IPAQ) and basal metabolic
rate, estimated by Schoeld’s e quation (41) and taking into account
age, sex, and BMI. e ratio of energy intake to energy require-
ment was calculated, and participants with a ratio below 0.35 or
above 1.93 were excluded (N=1,099). Finally, only participants
living in mainland France and having complete data to calculate
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the nutritional quality scores were included. e nal sample
included 34,442 participants, with 22,813 women and 7,569 men.
Sociodemographic and lifestyle characteristics along with
food and nutrient intakes were presented across the provegetar-
ian score quintiles. For descriptive purposes, nutrient and food
data were adjusted for total energy intake by sex using the residual
method (40). Means, SDs and percentages were provided as
appropriate. P values referred to the Mantel–Haenzel chi-square
trend test for categorical variables and to the linear contrast test
(ANCOVA) for continuous variables.
e contributions (as percentages) of dierent food groups to
diet-related GHG emissions and CED across provegetarian score
quintiles are presented. All P-trends were obtained with linear
contrast tests (ANCOVA).
As an interaction between the provegetarian score and
organic food consumption was observed (P≤0.0001), data were
stratied by the level of organic food consumption. Associations
between the provegetarian score and environmental impacts for
the overall sample and the stratied tertiles of the contribution
of organic consumption to the whole diet were estimated using
ANCOVA adjusted with Dunett’s test. All models were adjusted
for sex, age, and energy intake. In addition, the ratio of organic
food consumption as a continuous variable was included in the
stratied analyses to account for residual confounding. e ordi-
nal margins option was used. In all the analyses, the environmen-
tal indicators were log-transformed to improve the normality of
the distributions. e data are presented as adjusted means with
their 95% condence intervals. Unadjusted models are provided
in the Table S2 in Supplementary Material. Two-sided tests and a
P-value <0.05 were used for statistical signicance.
All analyses were performed using SAS soware (SAS Institute
Inc., Cary, NC, USA).
RESULTS
Individual Characteristics
Tabl e 1 presents sociodemographic and lifestyle characteristics
of the participants across provegetarian score quintiles. No dif-
ference in the sex distribution of participants across the quintiles
was observed. Participants with higher provegetarian scores were
more likely to be highly educated, physically active, non-smokers,
and moderate or non-drinkers. e Q5 of the provegetarian score
(reecting high consumption of plant food) included the highest
proportion of participants with the lowest monthly income per
household unit (<900 euros), while Q4 included the highest
proportion of participants with the highest monthly income
(>2,700 euros). e highest proportion of participants living in
population-dense urban units was found in the Q4. Finally, the
largest share of vegetarians was included in the Q5 of the proveg-
etarian diet (8.3% in Q5 versus 0.2% in Q1).
Food and Nutrients Intake by
Provegetarian Score Quintile
Tables2 and 3 present food groups and nutrient intake across
provegetarian score quintiles. By construction, the consumption
of animal-based products decreased while the consumption of
plant-based products increased across quintiles. Participants in
the highest quintile also consumed less fast food products (ham-
burgers, pizzas, and sandwiches), sweets, and alcohol and had a
higher intake of salad dressings, popcorn, or nuts. Overall, con-
sidering nutrient intake, a higher provegetarian score was associ-
ated with a lower overall protein intake but a higher proportion
of plant protein (50.5% in Q5 versus 22.2% in Q1) and a higher
polyunsaturated fatty acid (PUFA) and monounsaturated fatty
acid (MUFA) intake as well as a lower saturated fatty acid intake
and higher n-6/n-3 PUFA ratio. e intake of carbohydrates and
ber increased across provegetarian score quintiles. Participants
in the Q5 of the provegetarian score also displayed the highest
level of organic food consumption, as organic food represented a
50% share of their total food consumption.
Considering vitamins and minerals, iron intake increased
across the quintiles of the provegetarian score while haem iron
decreased. As expected, participants in the Q5 of the provegetar-
ian score also exhibited a higher intake of most micronutrients
(β-carotene, B1, B6, B9, C, E, K vitamins, and minerals Mg, K, and
Mn). According to both the mPNNS-GS and PANDiet scores,
participants in the last quintile showed the highest adherence to
the French dietary guidelines.
Environmental Impacts by Provegetarian
Score Quintile
Aer the adjustment for energy intake, age, and sex, diet-related
GHG emissions, CED, and land occupation decreased across
the provegetarian score quintiles by −49.6, −26.9, and −41.5%,
respectively, between Q5 and Q1 (Ta bl e 4 ). For all indicators, a
linear association was observed (P<0.0001). is reects that
the richer a diet is in plant products, the lower the environmental
impacts are. For informational purposes, crude means and SDs of
environmental indicators across the quintiles of the provegetar-
ian score are presented in Figure S1 in Supplementary Material.
Contribution of Food Groups to Diet-
Related GHG Emissions, CED, and Land
Occupation by Provegetarian Score
Quintile
Figure1 indicates that the main contributor to diet-related GHG
emissions across the dierent provegetarian score categories was
animal-based products, particularly ruminant meat consump-
tion. Animal products were responsible for approximately
80% of the dietary GHG emissions for diets rich in animal
products (Q1 of the provegetarian score), between 70 and 80%
for diets moderate in animal products and approximately 60%
for diets rich in plant products (Q5 of the provegetarian score).
Specically, ruminant meat represented approximately half of
the diet-related GHG emissions, regardless of the type of diet
considered.
Concerning the CED (Figure2), consumption of fruits, and
vegetables was the major contributor (except for Q1 and Q2).
Estimates of the contribution of monogastric meat and ruminant
meat to diet-related CED were similar.
Finally, Figure3 presents land occupation by food group and
by quintile. e results were closer than those for GHG emissions,
TABLE 1 | Sociodemographic and lifestyle characteristics by provegetarian score quintile, N=34,442, BioNutriNet study, 2014.a
Q1 Q2 Q3 Q4 Q5 P-trendb
N (%) (17.8) (23.6) (20.2) (16.8) (21.6)
Provegetarian score
Mean 27.4 (2.5) 32.6 (1.1) 36.0 (0.8) 38.9 (0.8) 44.5 (3.5) <0.0001
Median (IQR) 28 (3) 33 (2) 36 (2) 39 (2) 44 (2)
Sex (%)
Female 75.8 75.5 75.2 75.3 76.0 0.81
Male 24.2 24.5 24.8 24.7 24.0
Age (years) 52.0 (14.0) 53.0 (14.1) 53.5 (14.0) 54.5 (13.6) 53.4 (14.1) <0.0001
Education level (%)
<High-school diploma 21.6 21.5 21.5 21.0 19.1 <0.0001
High-school diploma 15.9 15.4 14.3 13.8 14.1
Post-secondary graduate 62.5 63.1 64.1 65.2 66.8
Monthly income per household unit (%)
Refuse to declare 5.8 6.2 6.3 5.7 7.1 0.01
<900 euros 7.4 6.6 6.0 6.3 8.7
900–1,200 euros 5.2 4.4 4.6 4.4 4.7
1,200–1,800 euros 24.2 23.1 23.6 22.1 22.4
1,800–2,700 euros 27.3 27.7 26.7 27.7 26.9
>2,700 euros 30.1 31.9 32.9 33.7 30.3
Location (%)
Rural community 22.9 23.2 22.3 20.7 22.3 0.11
Urban unit with a population of <20,000 inhabitants 16.1 15.4 15.7 15.0 15.2
Urban unit with a population of 20,000–200,000 inhabitants 17.8 18.5 18.4 18.8 19.0
Urban unit with a population of >200,000 inhabitants 43.2 42.9 43.6 45.6 43.5
Physical activity (%)
Missing value 11.6 11.5 10.9 10.3 9.9 <0.0001
Low 22.9 21.7 19.5 17.4 15.2
Medium 35.3 36.3 37.2 37.2 37.2
High 30.2 30.5 32.4 35.1 37.6
Smoking status (%)
Non-smoker 48.6 48.5 48.4 48.6 49.3 0.04
Former smoker 13.3 11.6 11.2 9.7 9.0
Smoker 38.0 39.8 40.5 41.7 41.7
Alcohol intake (%)
Non-drinker 4.9 4.8 5.2 4.6 7.9 <0.0001
Moderate drinker (<20g/day for women and <30g/day for men) 83.5 86.0 86.1 88.0 85.8
High drinker (>20g/day for women and >30g/day for men) 11.6 9.2 8.7 7.4 6.4
Diet (%)
Vegetarians 0.18 0.39 0.83 1.46 8.27 <0.0001
Vegans 0.00 0.01 0.04 0.12 5.28
IQR, interquartile range; Q, quintile of provegetarian score.
aValues are presented as the mean (SD) or as a percentage.
bValues based on linear contrast test or γ2.
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showing a high contribution of animal products specically
ruminant meat to land occupation.
Moreover, the contribution of carbohydrates and oil to GHG
emissions and CED increased across the provegetarian score
quintiles. Of note, the contribution from cheese consumption was
more important than from the contribution from dairy products
and milk across quintiles.
Diet-Related Environmental Impacts
Considering both the Provegetarian Score
and the Level of Organic Food
Consumption
Tabl e 4 presents the association between the provegetarian score
and the environmental impacts stratied by the level of organic
food consumption. Similar linear trends were observed between
the provegetarian score and environmental impacts across
the dierent levels of organic food consumption. Considering
diet-related environmental impacts in diets that contained low
or moderate (Q1, Q2, and Q3) amounts of plant products (i.e.,
≥70% animal protein for protein intake and ≥45% animal lipid
for lipid intake), the level of organic food consumption did not
signicantly modify the association between the provegetarian
score and the environmental impacts (GHG: PQ2vsQ1=0.97 and
PQ3vsQ1=0.28; CED: PQ2vsQ1=0.94 and PQ3vsQ1=0.10; land occupa-
tion PQ2vsQ1=0.78 and PQ3vsQ1=0.97). However, for diets rich in
plant foods (Q4 and Q5), the dierences in the environmental
impacts across the provegetarian score quintiles increased across
the organic food ratio tertiles (P<0.0001 except for land occupa-
tion PQ4vsQ1=0.01).
TABLE 2 | Food and nutrient intake by provegetarian score quintile, N=34,442, BioNutriNet study, 2014.a
Q1 Q2 Q3 Q4 Q5 P-trendb
Nutrients intake
Energy intake without alcohol (kcal/day) 2,218.8 (638.5) 1,969.9 (597.1) 1,885.6 (614.0) 1,868.2 (599.6) 1,982.9 (613.6) <0.0001
Proteins (%)c20.7 (3.6) 19.5 (3.3) 18.5 (3.2) 17.5 (2.9) 15.6 (2.9) <0.0001
Plant proteins (% protein)c22.2 (6.3) 27.0 (7.3) 31.3 (8.3) 36.1 (9.3) 50.5 (17.9) <0.0001
Animal proteins (% protein)c77.8 (6.3) 73.0 (7.3) 68.8 (8.3) 63.9 (9.3) 49.5 (17.9) <0.0001
Lipids (%)c41.2 (6.4) 40.2 (6.7) 39.8 (7.1) 39.9 (7.2) 40.2 (7.5) <0.0001
Plant lipid (% of lipid)c34.4 (10.4) 40.7 (10.8) 46.1 (11.5) 51.2 (12.0) 63.3 (15.0) <0.0001
Animal lipid (% of lipid)c65.6 (10.4) 59.3 (10.8) 53.9 (11.5) 48.8 (12.0) 36.7 (15.0) <0.0001
PUFA (%)c5.6 (1.7) 6.1 (2.0) 6.4 (2.3) 6.9 (2.4) 8.3 (3.0) <0.0001
MUFA (%)c15.4 (3.2) 15.5 (3.6) 15.8 (4.0) 16.2 (4.2) 17.1 (4.6) <0.0001
SFA (%)c17.0 (3.5) 15.6 (3.1) 14.6 (3.1) 13.8 (3.0) 12.0 (3.1) <0.0001
Omega 3 (%)c2.0 (0.9) 2.2 (1.0) 2.3 (1.1) 2.5 (1.2) 3.0 (1.6) <0.0001
Omega 6 (%)c10.9 (3.0) 12.1 (3.5) 13.0 (3.9) 14.0 (4.0) 16.8 (5.1) <0.0001
Ratio n-6/n-3 6.3 (2.7) 6.5 (3.0) 6.6 (3.1) 6.5 (3.1) 6.7 (3.3) <0.0001
Carbohydrates (%)c35.3 (7.1) 37.5 (7.2) 39.0 (7.2) 40.0 (7.3) 41.9 (7.6) <0.0001
Fibers (%)c1.7 (0.5) 2.0 (0.6) 2.2 (0.6) 2.5 (0.7) 3.0 (0.8) <0.0001
Alcohol (g/day) 9.9 (14.8) 8.9 (12.6) 8.5 (13.2) 7.95 (10.7) 7.17 (10.3) <0.0001
Food consumption (g or ml/day)d
Vegetables and fruits 424.4 (301.7) 564.3 (314.9) 660.6 (346.0) 734.8 (354.1) 881.7 (420.0) <0.0001
Meat 165.3 (85.4) 139.4 (65.8) 123.3 (60.2) 109.2 (54.2) 71.9 (54.8) <0.0001
Ruminant (%) 36.0 (15.7) 35.4 (16.0) 35.3 (15.9) 34.2 (16.4) 32.1 (18.1) <0.0001
Pork (%) 42.1 (15.9) 41.8 (16.2) 41.1 (16.6) 41.4 (17.4) 40.8 (19.9) <0.0001
Poultry (%) 20.7 (13.9) 21.4 (14.5) 22.1 (15.5) 22.9 (16.1) 25.5 (19.3) <0.0001
Rabbit (%) 1.2 (2.4) 1.4 (2.7) 1.5 (2.7) 1.5 (2.6) 1.6 (3.7) <0.0001
Eggs 13.5 (15.2) 11.2 (11.7) 10.1 (10.8) 9.4 (9.8) 8.4 (11.0) <0.0001
Fish 53.6 (56.3) 49.3 (39.1) 47.1 (39.8) 45.4 (34.3) 37.4 (38.0) <0.0001
Dairy products 320.6 (248.1) 265.7 (209.3) 227.6 (184.4) 185.5 (161.0) 112.1 (145.0) <0.0001
Starchy food 159.9 (82.4) 179.1 (86.7) 189.8 (89.1) 194.6 (91.4) 213.1 (110.6) <0.0001
Whole cereal products 33.3 (54.2) 47.0 (62.0) 54.0 (62.4) 63.7 (68.0) 84.1 (81.7) <0.0001
Soy products 1.1 (54.2) 8.5 (61.7) 16.2 (76.8) 27.2 (97.7) 70.6 (140.7) <0.0001
Fast food 38.7 (48.1) 36.1 (31.6) 33.9 (33.1) 32.7 (29.0) 27.3 (24.2) <0.0001
Nuts 2.00 (8.63) 4.03 (8.93) 5.39 (10.79) 7.14 (13.19) 11.36 (15.25) <0.0001
Extra food (excluding nuts) 9.55 (9.26) 9.84 (9.80) 9.93 (9.51) 9.59 (9.99) 8.50 (9.07) <0.0001
Sweet products 80.6 (60.6) 77.3 (52.6) 74.0 (46.3) 69.7 (41.2) 61.9 (39.1) <0.0001
Oil 8.9 (12.2) 13.0 (12.5) 15.8 (13.3) 18.3 (14.1) 22.7 (15.5) <0.0001
Butter 8.6 (7.9) 7.4 (6.7) 6.7 (6.2) 6.2 (6.1) 4.5 (5.6) <0.0001
Other fats 2.4 (4.6) 2.3 (4.7) 2.4 (4.8) 2.1 (3.9) 2.1 (4.6) 0.1
Non-alcoholic drink 1571 (769) 1600 (763) 1590 (739) 1607 (731) 1591 (755) 0.1
Alcoholic drink 180.7 (162.6) 177.7 (142.6) 174.0 (144.4) 170.5 (118.5) 158.1 (114.8) <0.0001
Level of organic food consumption (in % of weight) 18.2 (19.8) 22.5 (22.2) 26.3 (24.2) 32.1 (26.4) 48.2 (30.7) <0.0001
Median of organic food consumption 12 17 21 26 48
IQR 26 32 36 41 53
mPNNS score (/13.5) 7.6 (1.87) 8.3 (1.73) 8.6 (1.67) 8.8 (1.66) 8.8 (1.68) <0.0001
PUFA, polyunsaturated fatty acid; MUFA, monounsaturated fatty acid; SFA, saturated fatty acid; IQR, interquartile range; Q, quintile of provegetarian score.
aValues are presented as the mean (SD).
bValues based on a linear contrast test.
cAs percent of energy intake.
dValues adjusted on the energy intake.
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DISCUSSION
In our study, participants with a high provegetarian score were
characterized by an overall healthier lifestyle, including healthier
diets, as reected by higher PANDiet and mPNNS-GS scores.
Diets rich in plant products displayed lower environmental
impacts (GHG emissions, CED and land occupation). Moreover,
the consumption level of organic products was shown to have a
positive moderating eect on diet-related environmental impacts
only in diets rich in plant-based food.
Overall, a higher provegetarian score was associated with lower
environmental impacts, particularly GHG emissions, across all
levels of organic food consumption. ese results at the individual
diet level were expected since livestock is the most substantial
agricultural contributor to GHG emissions, demands high energy
inputs, and requires important land resources (42–44).
Similar results for GHG emissions were documented in the
EPIC-Oxford observational study. However, the estimations were
not adjusted for energy intake, and the LCA did not consider the
production mode even though it included all stages of produc-
tion, transformation, and distribution. e authors showed that
a diet rich in animal products emitted 2.5 times as much GHG
than a vegan diet. For women and men, GHG emissions from
the diets of meat-eaters were 46 and 51% higher, respectively,
than those of sh-eaters (or pesco-vegetarians), and 50 and 54%
higher, respectively, than those of vegetarians (45). Other studies
TABLE 3 | Consumption of micronutrients by provegetarian score quintile, N=34,442, BioNutriNet study, 2014.a
Q1 Q2 Q3 Q4 Q5 P-trendb
Vitaminsc
Retinol (μg/day) 769.42 (1,530.30) 667.23 (1,052.50) 590.84 (420.54) 558.82 (362.70) 432.86 (353.49) <0.0001
β-carotene (μg/day) 2,685.90 (2,025.9) 3,579.01 (3,040.9) 4,175.05 (2,459.7) 4,677.09 (2,956.2) 5,872.50 (3,443.6) <0.0001
Vitamin B1 (mg/day) 1.33 (0.40) 1.35 (0.40) 1.35 (0.38) 1.37 (0.38) 1.48 (0.52) <0.0001
Vitamin B2 (mg/day) 2.47 (0.70) 2.31 (0.61) 2.20 (0.55) 2.13 (0.52) 1.99 (0.51) <0.0001
Vitamin B3 (mg/day) 26.61 (8.44) 26.21 (7.29) 25.70 (6.68) 25.64 (6.41) 24.23 (6.30) <0.0001
Vitamin B5 (mg/day) 6.76 (1.65) 6.54 (1.44) 6.39 (1.33) 6.26 (1.23) 6.06 (1.19) <0.0001
Vitamin B6 (mg/day) 1.91 (0.50) 1.96 (0.47) 1.99 (0.46) 2.04 (0.46) 2.17 (0.56) <0.0001
Vitamin B9 (μg/day) 317.56 (122.44) 359.11 (123.69) 385.77 (116.52) 410.20 (123.12) 482.06 (157.47) <0.0001
Vitamin B12 (μg/day) 8.69 (9.07) 7.67 (6.41) 6.96 (3.14) 6.57 (2.77) 5.23 (2.93) <0.0001
Vitamin C (mg/day) 104.49 (70.41) 126.24 (70.54) 141.66 (81.21) 151.66 (78.85) 174.60 (90.83) <0.0001
Vitamin D (μg/day) 3.55 (2.22) 3.24 (1.63) 3.08 (1.70) 2.97 (1.47) 2.54 (1.63) <0.0001
Vitamin E (mg/day) 9.66 (4.36) 11.59 (4.37) 12.74 (4.63) 13.76 (4.63) 16.44 (5.67) <0.0001
Vitamin K (μg/day) 142.59 (122.15) 187.11 (143.88) 217.57 (140.31) 244.35 (205.46) 310.09 (201.96) <0.0001
Mineralsc
Ca (mg/day) 1,172 (391) 1,094 (329) 1,044 (304) 998 (282) 915 (261) <0.0001
Fe (mg/day) 14.23 (3.78) 14.92 (3.44) 15.25 (3.25) 15.83 (3.40) 17.36 (4.00) <0.0001
Haem Fe (mg/day) 1.97 (1.62) 1.68 (0.85) 1.50 (0.75) 1.36 (0.67) 0.94 (0.65) <0.0001
I (μg/day) 160.20 (280.37) 177.08 (211.47) 193.07 (275.48) 203.11 (309.02) 329.66 (710.17) <0.0001
Mg (mg/day) 444.43 (138.26) 470.93 (134.19) 482.83 (130.29) 502.58 (132.78) 540.85 (140.23) <0.0001
P (mg/day) 1,550.19 (315.86) 1,471.20 (270.59) 1,420.12 (255.63) 1,379.49 (238.06) 1,322.24 (234.55) <0.0001
K (mg/day) 3,508.30 (840.07) 3,645.63 (825.93) 3,726.91 (831.23) 3,802.52 (835.48) 3,961.31 (904.80) <0.0001
Na (mg/day) 2,739.20 (592.86) 2,641.56 (492.86) 2,570.26 (491.03) 2,515.43 (475.96) 2,290.61 (550.78) <0.0001
Cu (mg/day) 1.74 (1.48) 1.90 (1.09) 1.98 (0.58) 2.10 (0.54) 2.38 (0.62) <0.0001
Zn (mg/day) 13.98 (3.13) 13.30 (2.60) 12.81 (2.31) 12.52 (2.19) 11.85 (2.23) <0.0001
Mn (mg/day) 3.65 (1.93) 4.40 (1.95) 4.84 (1.91) 5.32 (2.01) 6.53 (2.47) <0.0001
Se (μg/day) 83.19 (26.28) 80.68 (20.30) 78.94 (20.02) 78.04 (18.69) 75.43 (19.51) <0.0001
PANDiet score (/100) 62.43 (5.13) 64.90 (5.99) 66.37 (6.72) 67.99 (7.07) 71.12 (7.13) <0.0001
aValues are presented as the mean (SD).
bValues based on a linear contrast test.
cEnergy-adjusted mean (SD).
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documented similar trends in regards to environmental impacts
of modeled substitutions for meat (46–48). For instance, the mod-
eled substitution in the EPIC-Netherlands cohort demonstrated
that substituting meat with 35g/d of dierent combinations of
plant products including potatoes, pasta, vegetables, nuts, and
milky desserts could reduce GHG emissions up to 12% (49). In a
recent review, authors concluded that the isocaloric substitution
of meat by starchy food, fruits, nuts, and vegetables was more
sustainable in terms of GHG emissions. However, in that same
review, production modes (more or less agro-ecological modes)
were not distinguished (43).
Livestock results in GHG emissions such as nitrous oxide,
carbon dioxide, and methane due to high-energy feed production,
concentrating production and enteric fermentation of ruminants
(3). However, impacts related to ruminant meat are higher when
compared to monogastric animals because of methane emissions
and the need for substantial livestock feed production needed (43,
50, 51). As consumers in the Q5 of the provegetarian score ate less
meat, especially ruminant meat, compared to participants in the
other quintiles, the dierence in GHG emissions is further increased.
A previous study showed that a diet in which ruminant meat is
replaced by monogastric meat (pork or poultry) reduced GHG
emissions from 20 to 35% and land-use impacts from 30 to 50% (50).
In another study, the CED was computed at the farm level
using the LCA method, and it was shown that a 60% decrease
in daily meat consumption that is replaced by planted-based
products led to an up to 38% decrease in CED, according to
various scenarios of self-suciency in Austria (48). e review
by Perignon etal., which covers 10 cohort studies on the environ-
mental impact of observed individual diets, demonstrates that
low-meat diets are more environmentally friendly (43).
Livestock farming requires a substantial input of fossil energy
due to farm facilities and production of feed (3). Moreover, plant
products have higher energy eciency when considering the ratio
of outputs/inputs for each calorie (52). Regarding the CED by
food group and by quintile, there is no clear dierence in the CED
contribution between ruminant meat and monogastric meat.
Considering the level of consumption, food group contribution
to CED is probably driven more by the dierence in intake than
energy use for the dierent types of meat since the dierences
they are less noticeable than for GHG emissions (53).
Finally, similar results on land use were found when the aver-
age Danish diet was replaced by the new Nordic diet containing
35% less meat with a 24% decrease in diet-related land use. In
the model performed for the EPIC-Netherlands cohort, the
substitution of meat with 35g/d of plant products led to an up to
12% decrease in land use (49). Moreover, the review of Hallström
et al., which included 14 original studies (mainly based on
modeling methods), showed that vegan diets reduced land use
up to 60 and 50% for men and women, respectively (50). In fact,
livestock farming is the largest user of land due to the total area
need for grazing and feed crop production (5).
TABLE 4 | Association between provegetarian score tertile and environmental impacts according to the level of organic food consumption, BioNutriNet study, 2014.
Overall Level of contribution of organic food to the diet
Low (0.03) Medium (0.23) High (0.63)
Meana95% CL Meana95% CL Meana95% CL Meana95% CL
Greenhouse gas emissions (CO2eq/day)
Q1 provegetarian score
Q2 provegetarian score
Q3 provegetarian score
Q4 provegetarian score
Q5 provegetarian score
Pb interaction <0.0001
Pc Q1 vs Q2 0.9711
Pc Q1 vs Q3 0.2764
Pc Q1 vs Q4 <0.0001
Pc Q1 vs Q5 <0.0001
Cumulative energy demand (MJ/day)
Q1 provegetarian score
Q2 provegetarian score
Q3 provegetarian score
Q4 provegetarian score
Q5 provegetarian score
Pb interaction <0.0001
Pc Q1 vs Q2 0.9417
Pc Q1 vs Q3 0.1044
Pc Q1 vs Q4 <0.0001
Pc Q1 vs Q5 <0.0001
Land occupation (m2/day)
Q1 provegetarian score
Q2 provegetarian score
Q3 provegetarian score
Q4 provegetarian score
Q5 provegetarian score
Pb interaction <0.0001
Pc Q1 vs Q2 0.7782
Pc Q1 vs Q3 0.9696
Pc Q1 vs Q4 0.0111
Pc Q1 vs Q5 <0.0001
Models are adjusted on sex, age, and energy intake.
aAdjusted means were obtained with ANOVA models by the level of organic food contribution in the diet. P-trends across the provegetarian score quintile are all <0.0001 and were
obtained with a linear contrast test by the level of organic food contribution in the diet.
bP for interaction between provegetarian score quintiles and the level contribution of organic food to the diet.
cP-linear trend of Q*v.Q1 of provegetarian score. It reflects the linearity of the difference between the first and the other quintiles of the provegetarian score across the levels of
organic consumption.
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It is worth noting that beyond the benets to the environment,
diets rich in plant products also provide important nutritional
and health benets (54, 55).
We showed that introducing organic food to one’s diet had a
signicant positive environmental eect on GHG emissions in
only diets rich in plant products. However, when considering a
diet with a moderate amount of plant products, this eect was
not substantial.
e weak moderating eect of the organic consumption in a
diet with a moderate amount of plant products can be explained
by several hypotheses. First, no dierence in GHG emissions was
reported for both conventional and organic beef and milk produc-
tion systems (20). In addition, GHG emissions from chicken and
pork organic farming practices are higher because feed produc-
tion is more substantial due to a longer cycle of production and a
lower growth rate (in relation to a lower feed-eciency conver-
sion) (20). Moreover, GHG emissions from organic pork farming
practices can be higher because of the high level of nitrous oxide
emissions from straw litter (19). However, the dierences between
chicken and pork production systems have not yet been consist-
ently measured, and further research is needed to improve the
reliability of calculating GHG emissions for dierent farming
practices. Second, organic farming results in lower GHG emissions
when emissions are expressed by units of area, and no clear trends
emerge when they are expressed by units of product weight (18).
Finally, organic practices have obvious benecial eects on GHG
emissions in terms of plant production because of the exclusion
of synthetic fertilizers that result in high N2O and CO2 emissions
(19, 56). Finally, the proportion of organic food consumption in
the diet may be too low in the rst provegetarian score quintiles
to detect dierences in GHG emissions. Considering the CED
indicator, the ratio of organic food in the diet positively aects
diet-related environmental impacts with increasing eects across
provegetarian score quintiles. Organic practices prohibit the use
4.56 (4.51–4.60) 4.59 (4.53–4.65) 4.56 (4.48–4.63) 4.10 (3.99–4.22)
4.05 (4.01–4.08) 4.13 (4.08–4.18) 4.05 (4.00–4.10) 3.74 (3.66–3.81)
3.62 (3.62–3.66) 3.73 (3.68–3.78) 3.68 (3.63–3.74) 3.34 (3.28–3.41)
3.23 (3.20–3.27) 3.45 (3.39–3.51) 3.38 (3.33–3.43) 2.94 (2.89–2.99)
2.27 (1.33–2.29) 2.93 (2.87–2.99) 2.72 (2.67–2.76) 2.12 (2.09–2.14)
18.55 (18.43–18.67) 18.58 (18.40–18.75) 18.58 (18.39–18.78) 17.33 (17.05–17.63)
17.43 (17.33–17.53) 17.62 (17.47–17.77) 17.47 (17.32–17.63) 16.53 (16.32–16.73)
16.48 (15.52–16.58) 16.87 (16.70–17.04) 16.62 (16.47–16.78) 15.59 (15.41–15.77)
15.62 (15.52–15.73) 16.42 (16.21–16.63) 16.10 (15.93–16.27) 14.62 (14.45–14.78)
13.29 (13.21–13.37) 15.56 (15.33–15.79) 14.72 (14.56–14.89) 12.66 (12.56–12.76)
11.33 (11.14–11.41) 10.94 (10.78–11.10) 11.58 (11.39–11.78) 11.66 (11.36–11.96)
10.26 (10.17–10.35) 9.89 (9.76–10.03) 10.31 (10.17–10.45) 10.64 (10.45–10.85)
9.34 (9.26–9.43) 8.95 (8.81–9.09) 9.43 (9.29–9.57) 9.61 (9.44–9.79)
8.51 (8.42–8.60) 8.26 (8.10–8.43) 8.68 (8.54–8.83) 8.50 (8.35–8.65)
6.63 (6.57–6.69) 7.03 (6.87–7.19) 7.09 (6.97–7.21) 6.49 (6.41–6.57)
FIGURE 1 | Greenhouse gas (GHG) emissions by food group and by quintile of provegetarian score. Other food group includes whole products, soy products,
eggs, butter, other fats, and alcohol. Food group impacts are all significant (P-trend<0.05).
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of synthetic fertilizers which induce high costs in energy for their
production and require the use of less mineral fertilizers and feed
concentrates (56). However, some studies have determined that
CED can be up to 40% higher in organic farming than in conven-
tional systems (19). Another explanation relies on the fact that
among the high consumers of organic foods, plant-based food
consumption was higher overall. However, the correlation coef-
cient between the provegetarian score and the level of organic
food consumption was estimated to be 0.4.
Regarding land occupation, the level of organic food consump-
tion had a positive impact on diets rich in plant products and had
no impact on diets with moderate level of plant product intake.
ese ndings are noteworthy since organic systems require
relatively more land (20, 56, 57) than conventional production
systems. ese lower crop yields are due to lower total nitrogen
inputs per hectare (20). Our results may be explained by the fact
that in the Q5 of the provegetarian score, consumers that eat a
substantial amount of organic food exhibited higher plant-based
consumption than their conventional counterparts and thus
may have exhibited a lower consumption of meat. Moreover,
according to Pimentel and Pimentel, grains and some legumes,
which were highly consumed by participants in the Q5 of the
provegetarian score, are produced more eciently than fruits and
vegetables (42). is may have led to a reduction in the negative
impact of organic production on plant production yields. e
absence of a dierential eect of organic food consumption on
land use for a diet with a moderate amount of plant products
may be related to the fact that the ratio of organic foods in the
diet is too low to detect any association, which is the same for
GHG emissions. ese ndings regarding land occupation need
further investigation since future improvements of management
techniques and crop varieties may reduce the dierence in crop
yields between organic and conventional systems (9). Although
this was not evaluated in our study, organic systems generally oer
environmental services, do not use pesticides, increase resilience
of agriculture and can mitigate the future eects of climate change
on yields (58).
e limitations of this study should be noted. An extrapo-
lation of these results to the general population should be
done with caution as the participants who completed the
BioNutriNet questionnaires were probably more concerned
with nutrition and health-related issues. It should be noted that
the percentage of participants with a very high consumption of
organic foods, as observed in our study, is likely to be minimal
in France. e use of a food frequency questionnaire may be
prone to incorrectly estimating habitual diets, which is similar
to other self-reported food consumption tools (59). Moreover,
the eects of the systems of production on the environment
should be considered with caution. Indeed, among similar
systems of production, eects can be largely dierent due to
climate conditions, soil types and farm management (18, 56).
Other indicators such as pesticide use, leaching, and soil qual-
ity would have been relevant to addressing the environmental
impacts of production systems (60, 61). In addition, our data
included neither the origin nor the seasonality of food products,
which may impact environmental assessments. Furthermore,
FIGURE 3 | Land occupation by food group and by quintile of provegetarian score. Other food group includes whole products, soy products, eggs, butter, other
fats, and alcohol. Food group impacts are all significant (P-trend<0.05).
FIGURE 2 | Cumulative energy demand by food group and by quintile of provegetarian score. Other food group includes whole products, soy products, eggs,
butter, other fats, and alcohol. Food group impacts are all significant (P-trend<0.05).
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environmental impacts were assessed at the farm level and did
not consider all of the production, transformation and distribu-
tion stages.
However, our study also presents notable strengths. First, to
the best of our knowledge, this is the rst study to distinguish
production modes in the assessment of food consumption
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and several subsequent environmental impacts. is is also
the rst study to investigate moderating eects of organic
food consumption on the environmental impact of observed
diets. Modeling studies do not necessarily consider isocaloric
or representative substitutions. For example, replacing meat
with fruit and legumes may not appear entirely realistic. Meat
would probably be replaced by energy-dense products such
as cereals, potatoes, and legumes. Moreover, these modeling
studies rely on small cohorts. erefore, it was crucial to focus
on actual diets assessed in a large cohort to conrm or refute
the results from modeling studies. Concerning the strengths of
this study, our study is based on a large sample, which allows a
wide diversity of dietary behaviors to be considered and in par-
ticular eco-friendly behaviors, using accurate environmental
and consumption data. e provegetarian score also presents
several advantages when compared to other dietary indexes
commonly used in the literature such as the Mediterranean diet
score (62). Indeed, while the Mediterranean diet recommends
limiting milk and red meat, it also recommends consuming
sh even though a major part of the shing industry is not
sustainable (63) and degrades maritime ecosystem functions
by altering the food chain and sh habitats (64). Finally, the
provegetarian score reects dierent emerging dietary patterns
(e.g., exitarian diets) that tend to reduce consumption of
animal products.
In conclusion, diet-related GHG emissions, CED, and land
occupation indicators are negatively associated with a plant-
based diet, regardless of the level of organic food consumption.
Furthermore, the consumption of organic food showed additional
benecial impacts only in diets rich in plant products. is study
demonstrates that the environmental impacts of diets should not
only be evaluated in terms of dietary patterns but also should
integrate production systems.
ETHICS STATEMENT
e design was conducted according to the guidelines laid
down in the Declaration of Helsinki and was approved by the
Institutional Review Board of the French Institute for Health and
Medical Research (IRB INSERM no. 0000388FWA00005831) and
the “Commission Nationale de l’Informatique et des Libertés”
(CNIL no. 908450 and no. 909216). All participants signed an
electronic informed consent.
AUTHOR CONTRIBUTIONS
EK-G, SH, PP, and DL designed the research; CL, LS, BA, BL,
PP, DL, JB, and EK-G conducted the research; CL, LS, BA, JB,
and EK analyzed the data; and CL and EK wrote the paper. CL,
LS, BA, BL, PP, DL, JB, and EK were involved in interpreting the
results and editing the manuscript. CL, LS, and EK had primary
responsibility for the nal content. All authors read and approved
the nal manuscript.
ACKNOWLEDGMENTS
We especially thank Younes Esseddik, Paul Flanzy, and i Hong
Van Duong, computer scientists; Veronique Gourlet, Fabien
Szabo, Nathalie Arnault, Laurent Bourhis, and Stephen Besseau,
statisticians; and Cédric Agaësse and Claudia Chahine, dieti-
cians. We warmly thank all of the dedicated and conscientious
volunteers involved in the Nutrinet-Santé cohort.
FUNDING
e BioNutriNet project was supported by the French National
Research Agency (Agence Nationale de la Recherche) in the con-
text of the 2013 Programme de Recherche Systèmes Alimentaires
Durables (ANR-13-ALID-0001). e NutriNet-Santé cohort
study is funded by the following public institutions: Ministère
de la Santé, Santé Publique France, Institut National de la Santé
et de la Recherche Médicale (INSERM), Institut National de la
Recherche Agronomique (INRA), Conservatoire National des
Arts et Métiers (CNAM) and Paris 13 University. e funders
had no role in study design, data collection and analysis, decision
to publish, or preparation of the manuscript.
SUPPLEMENTARY MATERIAL
e Supplementary Material for this article can be found online
at http://www.frontiersin.org/articles/10.3389/fnut.2018.00008/
full#supplementary-material.
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