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RESEARCH
Research and Professional Briefs
Young Swedish Vegans Have Different Sources of
Nutrients than Young Omnivores
CHRISTEL L. LARSSON, PhD; GUNNAR K. JOHANSSON, DDS
ABSTRACT
The aim of this study was to identify sources of nutrients
in diets of young Swedish vegans and omnivores. Three
months of dietary intakes were investigated by diet history interviews. Volunteers were recruited through advertising and visits to schools in the city of Umeå, Sweden. Thirty vegans, 15 female and 15 male, aged 17.5⫾1.0
years, were compared with 30 sex-, age-, and heightmatched omnivores. Vegans had different sources of nutrients than young omnivores and relied to a great extent
on dietary supplements as a source of vitamin B-12, vitamin D, calcium, and selenium. Dietary intake of vegetables, fruits, and berries exceeded 500 g/day for 21 of the
30 vegans, whereas the same held true for only 1 of the 30
omnivores. Instead of animal products, young vegans rely
on dietary supplements, legumes, vegetables, fruits, and
berries as sources of nutrients.
J Am Diet Assoc. 2005;105:1438-1441.
I
n the mid-1990s, an increasing number of young people
became vegans in Sweden (1). People eating a vegan
diet consume food products from the plant kingdom
only and exclude meat, fish, eggs, and dairy products (2).
The young vegans were eating vegan food mainly for
ethical reasons rather than health considerations. Because of this, there was apprehension that they excluded
animal products from their diet without replacing them
with nutritionally equivalent products from the plant
kingdom. This concern was based on speculations rather
than on scientific knowledge and, in order to obtain more
information, a study was conducted to gather data on the
food intake of young vegans.
Dietary intake of 30 vegans was investigated by diet
history interview and compared with that of 30 omnivores. Intake for the female group of vegans showed that
contributions from diet alone of vitamin B-12, vitamin D,
calcium, and selenium were below average requirements
(3). When consumption of dietary supplements was in-
C. L. Larsson is a senior lecturer and G. K. Johansson
is a professor, Department of Food and Nutrition, Umeå
University, Umeå, Sweden.
Address correspondence to: Christel Larsson, Department of Food and Nutrition, Umeå University, SE-901
87 Umeå, Sweden. E-mail: [email protected]
Copyright © 2005 by the American Dietetic
Association.
0002-8223/05/10509-0012$30.00/0
doi: 10.1016/j.jada.2005.06.026
1438
Journal of the AMERICAN DIETETIC ASSOCIATION
cluded, however, intakes of vitamin B-12, vitamin D, and
calcium were above average requirements. Selenium obtained from both diet and supplements provided 79% of
the average requirement. For female omnivores at group
level the dietary intake from diet alone was above average requirements for all nutrients except selenium.
Intake at group level of male vegans showed that the
contribution from diet alone of vitamin B-12, riboflavin,
calcium, and selenium was below average requirements
(3). Calcium and selenium obtained from both diet and
supplements provided 98% and 65% of the average requirement, respectively. Intake of vitamin B-12 and riboflavin was above average requirements when intake from
dietary supplements was included. For male omnivores,
the dietary intake at group level was above average requirements for all nutrients.
It is of interest to further analyze the dietary data
collected to identify sources of nutrients and choice of
vegetables and fruits in diets of young Swedish vegans
and omnivores. The method of analysis and sources of
nutrients are presented and discussed in this article.
SUBJECTS AND METHODS
Subjects
Volunteers, who had to be 16 to 20 years old and in good
health with no chronic diseases, were recruited
through poster advertising and visits to schools in the
Umeå area. Vegans were defined as people eating food
of plant origin only, and they were included in the
study if they had consumed a vegan diet for at least 6
months and were planning to continue. Omnivores
were defined as people eating food of both plant and
animal origin. They were considered for participation
in the study if they had consumed an omnivorous diet
through their entire life and were planning to continue
to do so. No lacto-ovo-vegetarians or individuals with
dietary restrictions of special diets for weight loss,
lactose intolerance, or other conditions were included
among the group of omnivores. In total, 65 self-described vegans and 272 omnivores were interviewed
regarding food habits, age, and height. Thirty vegans
were eligible for inclusion according to the above-mentioned inclusion criteria. Thereafter, 30 omnivores
were matched by sex, age (⫾6 months), and height
(⫾3.5 cm). Background data for the subjects have been
published previously (4). Each participant gave written
informed consent and the study was approved by the
research ethics committee of the Medical Faculty,
Umeå University, Umeå, Sweden.
© 2005 by the American Dietetic Association
Figure. Contribution to nutrient intake of different food categories eaten by 30 vegans and 30 omnivores in Umeå, Sweden. Categories are
presented in order from dietary supplements on the right in the stack bar to miscellaneous on the left. The miscellaneous category includes: mixed
dishes that could not be subdivided into food components, alcoholic drinks, oil, dressing, coffee, tea, salt, and spices. The animal product category
includes meat, fish, seafood, dairy products, and eggs.
Dietary Assessment
Each respondent was asked about usual food intake
during two separate 1- to 2-hour diet history interviews
1 to 2 weeks apart during the period August 1997 to
June 1998. The aim was to construct a typical eating
pattern for the preceding 3 months. No food records or
food frequency questionnaire was used. Rather, the
subjects reported in the first interview what type of
food they usually ate and how often. During the second
interview, portion sizes of foods were described in
terms of household measures, standard weights of food
items, three-dimensional food models, or portion photographs of known weights (5). The reported food, beverage, and dietary supplement intakes were entered in
the dietary analysis program Stor MATs 4.03e (Rudans
Lättdata, Västerås, Sweden), which uses the Swedish
Food composition database (version 2.97). Composite
foods (eg, casseroles) were split into ingredients (food
items). Each food item has a unique “food item code” in
the database and food items also have a “food category
code.” The program provides weight reports (in grams)
of various food categories. Recipes and information on
nutritional content of composite foods and dietary supplements not listed in the food database were added.
Further information about the dietary assessment, the
validity of the method, and information about energy
and nutrient intakes of the 60 subjects, has been published previously (3,4).
RESULTS
Sources of Nutrients
Sixteen percent of the vegan energy intake came from
low-nutritious food (such as candy, pastry, chips, and soft
drinks) compared with 22% of the omnivore energy intake
(Figure).
Vegans obtained 53% of protein intake from bread,
cereals, pasta, and rice; 24% from legumes; and 14%
from vegetables and potatoes, while the corresponding
figures for omnivores were 19%, 0%, and 3%, respectively (Figure). A large amount (62%) of protein intake
in the omnivorous diet came from animal products.
All vitamin B-12 in the vegan diet came from dietary
supplements (Figure). The greatest food source of vitamin
D in the vegan diet was margarine (50%), while in the
omnivorous diet it was animal products (51%). The three
best food sources of iron in the vegan diet were the food
categories consisting of bread, cereals, pasta, and rice
(29%); vegetables and potatoes (16%); and legumes (15%);
the best sources for omnivores were bread, cereals, pasta,
September 2005 ● Journal of the AMERICAN DIETETIC ASSOCIATION
1439
Table. Comparison of Swedish vegans’ and omnivores’ choice of bread, cereals, vegetables, potatoes, fruits, and berries to identify sources
of nutrients
Bread, cereals, pasta,
and rice (rank)a
Vegans
(nⴝ30)
(g/d) %b
Semi whole-wheat bread 93
Rice
71
White bread
68
Pasta
57
Porridge
46
Crisp bread
42
Breakfast cereals
15
Gruel
4
Total
396
a
Omnivores
(nⴝ30) Vegetable and
potato intake
(g/d) %b (rank)a
23 60
18 33
17 61
14 40
12 42
11 23
4 23
1
0
100 282
21
12
22
14
15
8
8
0
100
Vegans
(nⴝ30)
(g/d) %b
Potatoes
137
Tomatoes
90
Cucumbers
40
Onions
37
Carrots
29
Iceberg lettuces
21
Peppers
20
Mushrooms
17
Zucchinis
13
Vegetable mixes
10
Leeks
10
Bean sprouts
9
Broccolis
8
Corn
8
Peas
7
Avocados
6
Cabbages
6
Aubergines
5
Chinese leaves
5
Beetroots
4
Pickled cucumbers
4
Asparagus
3
Cauliflowers
–
Lettuces
–
Spinach
–
Total
489
27
18
8
7
6
4
4
3
3
2
2
2
2
2
1
1
1
1
1
1
1
1
–
–
–
98
Omnivores Fruits and
(nⴝ30) berries
intake
(g/d) %b (rank)a
109
29
13
12
15
8
5
2
–
3
1
–
–
–
–
2
4
–
2
3
–
–
2
2
2
214
50
14
6
5
7
4
3
1
–
1
1
–
–
–
–
1
2
–
1
1
–
–
1
1
1
100
Vegans
(nⴝ30)
Omnivores
(nⴝ30)
(g/d) %b (g/d) %b
Apples
69
Bananas
36
Oranges
34
Pears
12
Melons
6
Grapes
5
Strawberries
3
Peaches
3
Raisins
2
Mangos
2
Plums
2
Figs
2
Blueberries
2
Apricots
1
Fruit cocktails
1
Kiwis
1
Pineapples
–
Raspberries
–
Total
181
38
20
18
6
3
3
1
1
1
1
1
1
1
1
1
1
–
–
98
49
46
32
10
–
3
–
–
2
–
–
–
–
1
–
3
4
1
151
32
30
21
7
–
2
–
–
1
–
–
–
–
1
–
2
3
1
100
Food items are ranked by largest intake of vegans.
Intake of a specific food item expressed as a percentage of the total amount of all food items in the present category.
b
and rice (26%) and animal products (25%). The largest
sources of calcium, zinc, and selenium for vegans were
dietary supplements, while animal products were the
largest sources in the omnivorous diet. However, the best
source of calcium from food in the vegan diet was vegetables and potatoes (15%), and 33% of the zinc intake and
14% of the selenium intake came from bread, cereals,
pasta, and rice.
Choice of Vegetables, Fruits, and Berries
Intake of pasta, rice, and crisp bread was statistically
higher (P⬍.05) among vegans than omnivores, while the
intake of breakfast cereals was lower (Figure). For 21 of
the 30 vegans, the dietary intake of vegetables (except
potatoes), fruits, and berries was above 500 g/day, which
conforms to the Swedish recommendation (6). The same
held true for only one of the 30 omnivores. Vegans ate
significantly more vegetables but not significantly more
fruits and berries than the omnivores. Vegans and omnivores tended to choose similar types of vegetables, fruits,
and berries in their diets, but vegans included a larger
variety (Table). The most common vegetables eaten were
tomatoes, cucumber, onions, carrots, and iceberg lettuce,
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September 2005 Volume 105 Number 9
accounting for 42% and 36% of the intake for each group,
respectively. The most common fruits eaten by both vegans and omnivores were apples, bananas, oranges, and
pears, which accounted for 82% and 90% of the fruit
consumption, respectively.
DISCUSSION
Significantly lower intake of candy and chocolate was
seen among vegans compared with omnivores in the
present study. The same was found in Canadian and
American studies (7-9).
Legumes and bread were the greatest sources of protein for vegans in the present study and accounted for
11% and 24% of the protein intake, respectively. However, fruits, berries, and vegetables were also a great
source and accounted for 12% of the protein intake. These
results may be compared with findings of another study
of lacto-ovo-vegetarians in which legumes, bread/cereals,
and fruits/vegetables accounted for 39%, 19%, and 14% of
protein intake, respectively (7).
Similar to the results of other studies (10,11), the main
food sources of iron were found to be bread (19%) and
fruits, berries, and vegetables (14%). However, dietary
supplements were also a major contributor to iron intake
(22%), as well as to selenium, zinc, calcium, vitamin D,
and vitamin B-12 intake (12).
Both male and female vegans showed a statistically
significant, higher intake of vegetables compared with
omnivores. This result is similar to the findings of a study
on 14- to 19-year-old Canadian adolescents in which 78
lacto-ovo-vegetarians had a higher intake of vegetables
than 29 omnivores (7). In the present study, there was no
significant difference in fruit and berry consumption
among vegans compared with omnivores. This was also
shown by Donovan and Gibson, but does not verify results
of an American study of vegetarians aged 12 to 20 years
(7-9), which showed that vegetarians were twice as likely
to consume fruits (excluding juice). In this study, the
vegans tended to consume the same types of vegetables
and fruits as the omnivores; however, the vegans consumed a larger number of different fruits and vegetables
than the omnivores.
CONCLUSIONS
The young Swedish vegans in the present study did not
exclude meat and animal products without replacing
them with nutritious alternatives. Rather, they had different sources of nutrients than the young omnivores,
such as dietary supplements, vegetables, legumes, nuts,
and seeds. For vegans, as well as omnivores, there may be
very different food patterns. However, if the diet is well
planned, both a vegan diet supplemented with vitamin
B-12 and an omnivorous diet can offer an adequate nutritional intake.
Meeting energy needs and limiting the intake of nutrient-poor foods are important considerations in the planning of a vegan diet. Also, a dietary supplement of vitamin B-12 is recommended and one needs to ensure that
intake of iron, calcium, zinc, and selenium is sufficient.
When planning menus for young vegetarians it is also
important to consider that adolescents often consume a
lot of food as snacks and meals away from home. Portable
snacks (eg, dried and fresh fruits, nuts and almonds,
hummus on pita bread, and juice) can make it easier for
vegetarian adolescents to have access to nutritious food
sources.
The authors would like to thank all the adolescents who
participated. The Faculty of Social Sciences at Umeå
University and the Swedish Foundation for Healthcare
Science and Allergy Research supported the present
study.
References
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