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Public Health Nutrition: 25(5), 1310–1320 doi:10.1017/S136898002100197X
Pattern analysis of vegan eating reveals healthy and unhealthy
patterns within the vegan diet
Catherine T Gallagher, Paul Hanley and Katie E Lane*
Research Institute for Sport and Exercise Sciences, I. M. Marsh Campus, Liverpool John Moores University, Barkhill
Road, Aigburth, Liverpool L17 6BD, UK
Submitted 7 September 2020: Final revision received 1 April 2021: Accepted 5 May 2021: First published online 11 May 2021
Abstract
Objective: This study aimed to identify the types of foods that constitute a vegan
diet and establish patterns within the diet. Dietary pattern analysis, a key instru-
mentforexploringthecorrelationbetweenhealthanddisease,wasusedtoidentify
patterns within the vegan diet.
Design: A modified version of the EPIC-Norfolk FFQ was created and validated to
include vegan foods and launched on social media.
Setting: UK participants, recruited online.
Participants:Aconveniencesampleof129vegansvoluntarilycompletedtheFFQ.
Collected data were converted to reflect weekly consumptionto enable factor and
cluster analyses.
Results: Factor analysis identified four distinct dietary patterns including: (1) con-
venience (22%); (2) health conscious (12%); (3) unhealthy (9%) and (4) tradi-
tional vegan (7%). Whilst two healthy patterns were defined, the convenience
patternwasthemostidentifiablepatternwithaprominenceofveganconvenience
mealsandsnacks,vegansweetsanddesserts,sauces,condimentsandfats.Cluster
analysis identified three clusters, cluster 1 ‘convenience’ (26·8%), cluster 2 ‘tradi-
tional’ (22 %)andcluster3‘healthconscious’(51·2%).Clusters1and2consistedof Keywords
an array of ultraprocessed vegan food items. Together, both clusters represent Dietary pattern analysis
almost half of the participants and yielding similar results to the predominant Vegan diet
dietary pattern, strengthens the factor analysis. Convenience
Conclusions:Thesenovelresultshighlighttheneedforfurtherdietarypatternstud- Traditional
ies with full nutrition and blood metabolite analysis in larger samples of vegans to Healthy
enhance and ratify these results. Ultraprocessed foods
Over half a million people in the UK (≈1% of the popula- Fe, Ca, iodine, n-3, Se and Zn in poorly adapted or non-
(9)
tion) follow a vegan diet where all animal sources are sub- fortified vegan diets . In dietary terms, a traditional vegan
stituted withplant-basedalternatives.Veganismquadrupled diet refers to a diet that omits all products derived wholly
(1)
between 2014 and 2019 in the UK with 600 000 vegans orpartlyfromanimalorigin.Thedietfocusesmoreonwhole-
(2,3) (10)
reportedin2019 , whilethepopularityinvegandietscon- grains, pulses, fruit and vegetables . It remains unclear if
(4)
tinuestogrowworldwide .Thefoodindustryisresponding modern vegan dietary adaptation methods can deliver the
to this by producing more processed vegan food and drink samehealthadvantagesastraditionalvegandiets.Forexam-
(2,5)
products than ever before . In January 2021, ‘Veganuary’ ple, if vegans are choosing ultraprocessed vegan products
saw over 440 000 people in the UK committing to a vegan over more natural plant-based alternative sources, could
(6) (11)
diet , raising the profile of plant-based eating which has this compromise the overall quality of the vegan diet? .
(7)
been associated with a range of health benefits . Bywayofdefinition, ultraprocessed foods refer to products
It is reported that a well-planned vegan diet can meet all mostly or entirely formulated from substances derived
(8) (12)
the nutritional requirements necessary for health .Thereis from foods that typically contain little or no whole foods .
still some debate, however, about the nutritional quality of These products are usually high in saturated fat, sugar and
vegan diets and the risk of nutritional deficiencies, notably salt. The majority of these food items are also considered
(13,14)
some key micronutrients such as vitamin B ,vitaminD, poor sources of protein, fibre and micronutrients .
12
*Corresponding author: Email k.e.lane@ljmu.ac.uk
©TheAuthor(s),2021.PublishedbyCambridgeUniversityPressonbehalfofTheNutritionSociety.ThisisanOpenAccessarticle,distributedunder
the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distri-
bution, and reproduction in any medium, provided the original work is properly cited.
https://doi.org/10.1017/S136898002100197X Published online by Cambridge University Press
Pattern analysis of vegan eating study 1311
(30)
Studies over the past two decades have provided important Adaptation followed methods used by Dyett et al. in their
information on the diet quality of various types of vegetar- evaluation of a validated FFQ for self-defined vegans in the
ians, but no single study has addressed the quality of specific USA.VeganfooditemsavailableintheUKwereidentified
vegan diets. Orlich et al.(7) reveal Adventist vegans con- from mainstream UK supermarkets and vegan UK forums.
sumedthelowestamountsoffoodsandsnackshighinadded A collection of naturally vegan food products and newly
sugars and saturated fats, in comparison with non-vegetar- emerging ultraprocessed vegan products were included in
iansandothervegetariangroups.Thisargumentisconsistent the FFQ. Ten vegan volunteers in a UK university who met
with much of the literature surrounding vegan diets(15−18) the study criteria took part in an initial pilot study.
.
However, the main weakness with this research is that it is Feedback from the volunteers was taken on board to further
outdated and perhaps not considering the increasing variety modify the vegan FFQ. To further enhance validation of the
of processed food and drinks that are now available to vegan-adapted FFQ, a focus group of Health and Care
vegans. In 2018, the UK developed more vegan products Professions Council registered dietitians in the UK were then
(5) consulted. Modifications and additions to the food groups
thananyothernation .PopularUKsupermarketsarereact-
ing by producing vegan wines with a pledge to ensure their were made accordingly based on the dietitians comments
(19) to generate the finalised version of the vegan-adapted FFQ
full range is suitable for vegans in the coming years .In
(20) (see online supplemental material S1). Questionnaire instruc-
2019, Galaxy launched a vegan Mars bar in the UK ,
(21) tions stated that the FFQ must reflect dietary habits over the
and in 2020, Mc Donald’s launched its first vegan meal .
Thus, the production of vegan alternatives including vegan past month, and therefore, participants must have been fol-
snacks and fast foods is prevalent and represents one of the lowing a vegan diet for at least 1 month. Further questions
mainproductdevelopmenttrendswithinthefoodandretail were included such as motivations for adopting vegan life-
industry. However,manyofthesefooditemscanbehighin style, age, length of time vegan, cooking skills and supple-
saturated fats and sugars and if eaten regularly may pose a ment use to ensure evaluation of factors influencing diet
(31)
risk to health. Therefore, a review of current vegan dietary choice and nutritional knowledge .
patterns is urgently required to address these uncertainties.
Several studies have evaluated the dietary patterns of Recruitment
omnivores, pesco, lacto, ovo and semi-vegetarians in com- Online social media accounts (Instagram and Facebook)
(22−26)
parisonwithvegandiets , but nonetodatehassubjected wereusedtorecruitsubjects.TheFFQwaslaunchedonsocial
vegandietstodietarypatternanalysis.Itis important toestab- media accounts in the UK. The recruitment team asked for
lish whether the increased availability of processed vegan vegans in the UK to complete and share the FFQ. In order
replacementsforanimal-basedproductsisleadingtohabitual toreducebias,participants’involvementinthisstudywasvol-
consumption of an array of ultraprocessed foods. The meth- untary. Participants gave informed consent prior to complet-
odology for this unique study includes an innovative dietary ing the voluntary FFQ. Inclusion criteria required participants
pattern analysis of vegan diets. Dietary pattern analysis offers to be living in the UK and aged over 18 years, so only adults
aneffective way of understanding the diverse eating patterns could take part. Participants were also required to have fol-
within vegan diets by evaluating methods of adaptation and lowedavegandietforatleast1month.Thisallowedspecific
substitution(27). It was hypothesised that some vegan diets dietary patterns to be captured.
wouldincorporate a range of food groups representing a tra-
ditional well-planned vegan diet. This was expected to be the Statistical analysis
most common dietary pattern. The vegan food industry has
evolved; therefore, it was predicted that a convenience style Statistical analyses were performed using IBM SPSS(version
eating pattern could also emerge, representing a small pro- 26.0; SPSS Inc.) and Microsoft Excel 2013. Data screening
portion of the participants. and cleaning was conducted to check for any outliers and
This study aimed to identify patterns within the vegan errors on the categorical and continuous variables.
diet by establishing the everyday foods that vegans are Descriptive statistics such as frequencies and percentages
choosing to consume enabling an evidence-based evalu- were calculated for characterisation of the participants (i.e.
ation of the vegan diet. gender,agegroupsandlengthoftimevegan).Statisticaltests
were used to calculate the significance of error.
Methods Data screening
SelectedfrequencyofconsumptionforeachfoodintheFFQ
FFQ wascodedtoreflecthowofteneachitemwasconsumedper
AFFQwascreatedusingLJMU-approvedOnlinesurveytool, weekfordietarypatternanalysisasfollowed:NEVERorless
anonline food questionnaire creator, to enable the provision than once/month 0, 1–3/month, once a week, 2–4/week,
of a validated interactive dietary assessment tool(28). The vali- 5–6/week, once a day, 2–3/d, 4–5/d, 6þ/d. This design
datedEPIC-NorfolkFFQ(29)wasmodifiedtoincludequestions was taken from the validated EPIC-Norfolk FFQ, which
(32,33)
representative of foods and drinks suitable for vegans. hasalsobeenusedinotherstudies . Twomethodswere
https://doi.org/10.1017/S136898002100197X Published online by Cambridge University Press
1312 CT Gallagher et al.
Table 1 Food groups and food items included in the analysis of the FFQ cohort
Food groups 1 Food groups 2 (variables) Definition and content
1. Legumes & nuts 1. Protein alternatives to meat & Soya, Tempeh, Tofu, silken tofu, lentils, pulses, nuts, falafel
2. Meat alternatives fish
3. Meat-free processed alternatives 2. Processed meat alternatives Vegan nuggets, burgers, bacon, sausage, no fish fingers, ham
4. Fish alternatives slices, turkey slices, chicken slices, meat-free mince, vegan
chorizo
5. Vegan sandwiches 3. Convenience meals & snacks Garlic bread, pizza, sausage rolls, chips, ready prepared mash,
6. Vegan wraps selection of pre-made vegan sandwiches & wraps, ready
7. Ready-prepared foods meals, Not-zarrella sticks, French fries
8. Fresh fruit 4. Fruit Apples, pears, oranges, grapefruit, bananas, grapes, melon,
9. Tinned fruit peaches, strawberries, avocado, tinned fruit, dried fruit
10. Dried fruit
11. Vegetables 5. Vegetables Carrots, spinach, broccoli, Brussel sprouts, cabbage, peas,
12. Soup green beans, courgettes, cauliflower, parsnips, leeks, onions,
garlic, mushrooms, sweet peppers, beansprouts, green salad,
mixed vegetables, watercress, tomatoes, sweetcorn, beet-
root, coleslaw, vegetable soup, rainbow rice
13. Starchy carbohydrates 6. Refined grains White bread, scones, crackers, pitta, sugary cereal, plain cer-
eal, white rice, pasta, tinned pasta, noodles, lasagne, cereals
(except high fibre options)
14. High-fibre carbohydrates 7. Wholegrains Brown bread, wholemeal bread, porridge, all bran, wholegrain
cereals, brown rice, wholemeal pasta, wild rice
15. White potatoes 8. Potatoes Boiled potatoes, roast potatoes, sweet potatoes, home-made
16. Sweet potatoes mash, baked potatoes, baby potatoes
17. Plant-based milks 9. Dairy alternatives Oat milk, soya milk, almond milk, rice milk, hazelnut milk, coco-
18. Vegan cheese nut milk hemp, pea milk, Nutritional yeast, vegan hard
19. Vegan yoghurts cheese, Yoghurt alternatives,
20. Fats and oils 10. Fats and oils Vegan butter spreads, pesto, peanut butter, olive oil, sunflower
oil, coconut oil, avocado oil, canola oil, sunflower ghee, rape-
seed oil, fry light
21. Cakes & biscuits 11. Vegan cakes & biscuits Cookies, Digestive twists, bourbons, Lotus Biscoff, vegan
sponge cake, vegan cereal bars, party ring minis, granola
bars
22. Sweets and desserts 12. Vegan sweets & desserts Fudge, cheesecake pots, chocolate mousse pots, dark choco-
late, non-dairy ice cream, churros, star burst sweets
23. Vegan crisps 13. Vegan crisps Lentil Chips, Kettle chips, walkers, tortilla chips, vegetable
chips, pretzel bites
24. Sauces & condiments 14. Sauces and condiments BBQsauce,cheesesauce, Red lasagne sauce, free from
sauce, olive oil, vegetable oils, seeds, tahini, vegetable pates,
mayonnaise, hummus, chocolate spread, coleslaw, potato
salad
25. Salt 15. Salt All added salts
26. Alcohol 16. Alcohol Vegan friendly alcohols
27. Vegan takeaway 17. Vegan takeaway From fast-food outlets providing vegan options
28. Cooking 18. Cooking from scratch Additional question to help with establishing vegan patterns
29. Recipes used 19. Creating own recipes Additional question to help with establishing vegan patterns
30. Use of vegan brands 20. Purchasing vegan brands Additional question to help with establishing vegan patterns
used to classify the individual food items before applying used factor analysis as a statistical method to reduce large
factor and cluster analyses. In the first instance, the food sets of dietary intake variables into smaller sets of variables
(36,37)
and drink items were combined and collapsed into thirty that represent eating patterns . The smaller sets of
food groups and in the second twenty food groups composite variables derived through the principal compo-
(Table 1), respectively, with similar nutrient profiles, simi- nent method are referred to as ‘components’, and the
(34)
larly to previous research by Ashby-Mitchell et al. . variables within these are referred to as ‘factors’.The
Kaiser–Mayer–OlkinmeasureandBartlett’stestofsphericity
were undertaken before applying the principal component
Factor analysis method, to ensure the data were suitable for factor analy-
Factor analysis with the principal component method was (38)
sis . The twenty foodvariables fromfoodgroups2shown
performed in SPSS, with the procedure ‘dimension reduc- inTable 1wereenteredintothefactoranalysis.Obliminand
tion’ and ‘FACTOR’ on both sets of food groups to identify Varimax rotations were applied. The components derived
the primary components, which accounted for variation in from the Oblimin rotation were selected similar to previous
dietary intake. However, the smaller set of food groups (39,40)
work by researchers exploring dietary patterns .The
(n20)wasdeemedmoreappropriateduetothesmallsam- rotation redistributes the variance of each component
(35) (41)
plesize . Themethodsfollowedpreviousstudiesthathave allowing for a simpler structure . Oblimin rotation was
https://doi.org/10.1017/S136898002100197X Published online by Cambridge University Press
Pattern analysis of vegan eating study 1313
Fig. 1 Scree plot to show eigenvalues of each component number
chosenasthepreferredmethodof‘rotation’asithasarange Most participants were female (87%), and most were
(42)
of advantages compared with other types of rotation . aged18–24(36%)years.Themostcommonreasonselected
The number of components selected was based on the for following a vegan lifestyle was ‘Health, Environment &
assessmentofthescreeplot,withvalues>1deemedappro- Animalwelfare’(43%).Healthbenefitswereintheminority
priate to establish the patterns that explain the largest with only 3% following the vegan lifestyle primarily for
(36)
proportion of variance . Six components had an eigen- ‘health’. It is important to note that on the questionnaire,
value>1,buttherewasagradualbreakinthescreeplotafter these were presented as separate reasons and not a single
the fourth component (Fig. 1); therefore, four components reason. Participants were able to select more than one rea-
were retained. The dietary patterns were characterised by son.Mostvegans(41%)hadbeenfollowingavegandietfor
highandlowintakesofveganfoodanddrinks.Thepatterns 1–3years.Someparticipants(17%)wereeatingavegandiet
werelabelledbasedonthetypesoffactorsrepresentingthe for <6 months; (8%) 6–12 months; (23%) 4–10 years and
component and explanations in the literature. (11%) over 10 years. From those taking nutritional supple-
ments,themajoritytookvitaminB (68%).Almosthalftook
12
Cluster analysis vitaminD(42%).Amoderatenumber(26%)weretakingFe
Two-factor cluster analysis identifies groupings by running supplements and 19% took Ca supplements. A small num-
pre-clustering first and then by running hierarchical methods berofparticipants(15%,12%,14%and7%)consumedZn,
(35)
to enable automatic selection of the number of clusters . iodine, n-3 and Se supplements, respectively. Again these
Two-factor cluster analysis was performed to order the twenty micronutrientswerepresentedinalistonthequestionnaire,
food groups in a dendrogram, where food groups with the and participants were able to select more than one
highest correlations were further grouped together, while supplement.
samples with small correlations were widely separated. In
particular,thetwofoodgroupswiththelargestcorrelationwere
identified and merged into a single ‘synthetic’ sample. The Factor analysis
remaining food groups were then searched for the largest Inspection of the correlation matrix revealed the presence of
correlation with the synthetic sample. This process was manycoefficients of 0·3 and above. The Kaiser–Meyer–Olkin
(38)
repeated until all samples were merged into a single sample, value was 0·727, reaching the recommended value of 0·5
(44)
and the correlations among samples were then expressed as The Barlett’sTestofSphericity reached statistical signifi-
(43) cance,supportingthefactorabilityofthecorrelationmatrix(35).
a hierarchical tree .
Thedietarypatternswerecharacterisedbyhighandlow Factor analysis with the principal component method
intakes of vegan food and drinks. The clusters were revealed the presence of six components with eigenvalues
labelledbasedonthetypesofinputsrepresentingthecom- exceeding1,explaining22%,12%,9%,7%,7%and5%of
ponent and explanations in the literature. the variance. However, inspection of the scree plot (Fig. 1)
revealed a gradual break after the fourth component.
Therefore,thefirst fourcomponentsexplainthelargestpro-
Results portion of variance in the dietary intake data and were
retained as ‘dietary patterns’. Together these components
Participant characteristics represent a cumulative percentage of 50% of the inter-
Data collection took place from Monday 2 March 2020 individual variability. To aid the interpretation of these four
throughFriday3April2020.Therewere129fullycompleted components, oblimin rotation was performed, representing
FFQ. Sample characteristics are presented in Table 2. fourdefinite dietary patterns (Table 3). The first component
https://doi.org/10.1017/S136898002100197X Published online by Cambridge University Press
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